0
selected
-
1.
CpG and Non-CpG Methylation in the Diet-Epigenetics-Neurodegeneration Connection.
Fuso, A, Lucarelli, M
Current nutrition reports. 2019;(2):74-82
Abstract
PURPOSE OF REVIEW Unraveling the diet-epigenetics-neurodegeneration connection may disclose associated mechanisms and novel approaches to the neurodegenerative diseases. This review summarizes the basic concepts and the innovative results in this field focusing on the relevance of non-CpG methylation. RECENT FINDINGS Many multifactorial neurodegenerative diseases are associated with epigenetic changes, and the brain seems more prone to epigenetic changes than other tissues. Several environmental factors induce epigenetic modulation in the organisms: diet and nutrition retain a high capacity to modulate the epigenetic traits. Finally, unexpected, specific, and functional non-CpG methylation in the brain was identified. Non-CpG methylation modulates brain expression of genes especially in promoters characterized by low-density CpGs distribution. These genes appear more prone to the epigenetic effect of environmental factors, i.e., diet, possibly inducing neurodegenerative processes. Understanding these processes could help in setting nutritional intervention aimed at contrasting neurodegenerative diseases.
-
2.
An Evolutionary Perspective on Why Food Overconsumption Impairs Cognition.
Mattson, MP
Trends in cognitive sciences. 2019;(3):200-212
-
-
Free full text
-
Abstract
Brain structures and neuronal networks that mediate spatial navigation, decision-making, sociality, and creativity evolved, in part, to enable success in food acquisition. Here, I discuss evidence suggesting that the reason that overconsumption of energy-rich foods negatively impacts cognition is that signaling pathways that evolved to respond adaptively to food scarcity are relatively disengaged in the setting of continuous food availability. Obesity impairs cognition and increases the risk for some psychiatric disorders and dementias. Moreover, maternal and paternal obesity predispose offspring to poor cognitive outcomes by epigenetic molecular mechanisms. Neural signaling pathways that evolved to bolster cognition in settings of food insecurity can be stimulated by intermittent fasting and exercise to support the cognitive health of current and future generations.
-
3.
Anticancer potential of naturally occurring immunoepigenetic modulators: A promising avenue?
Schnekenburger, M, Dicato, M, Diederich, MF
Cancer. 2019;(10):1612-1628
-
-
Free full text
-
Abstract
The immune system represents the major primary defense line against carcinogenesis and acts by identifying and eradicating nascent transformed cells. A growing body of evidence is indicating that aberrant epigenetic reprogramming plays a key role in tumor immune escape through: 1) impaired efficient recognition of neoplastic cells by the immune system, resulting from a downregulation or loss of the expression of tumor-associated antigens, human leukocyte antigens, antigen processing and presenting machinery, and costimulatory molecule genes; 2) aberrant expression of immune checkpoint proteins and their ligands; and 3) modification of cytokine profiles and tumor-associated immune cell populations toward an immunosuppressive state in the tumor microenvironment. Consistent with the inherent reversibility of epigenetic alterations, epigenetic drugs, including DNA methyltransferase and histone deacetylase inhibitors, have the unique potential to favorably modify the tumor microenvironment, restore tumor recognition and stimulate an antitumor immune response. The objective of this review is to highlight selected, naturally occurring epigenetic modulators, namely, butyrate, curcumin, (-)-epigallocatechin-3-gallate, resveratrol, romidepsin, and trichostatin A, with a special focus on their antitumor immune properties.
-
4.
DNA phosphorothioate modification-a new multi-functional epigenetic system in bacteria.
Wang, L, Jiang, S, Deng, Z, Dedon, PC, Chen, S
FEMS microbiology reviews. 2019;(2):109-122
-
-
Free full text
-
Abstract
Synthetic phosphorothioate (PT) internucleotide linkages, in which a nonbridging oxygen is replaced by a sulphur atom, share similar physical and chemical properties with phosphodiesters but confer enhanced nuclease tolerance on DNA/RNA, making PTs a valuable biochemical and pharmacological tool. Interestingly, PT modification was recently found to occur naturally in bacteria in a sequence-selective and RP configuration-specific manner. This oxygen-sulphur swap is catalysed by the gene products of dndABCDE, which constitute a defence barrier with DndFGH in some bacterial strains that can distinguish and attack non-PT-modified foreign DNA, resembling DNA methylation-based restriction-modification (R-M) systems. Despite their similar defensive mechanisms, PT- and methylation-based R-M systems have evolved to target different consensus contexts in the host cell because when they share the same recognition sequences, the protective function of each can be impeded. The redox and nucleophilic properties of PT sulphur render PT modification a versatile player in the maintenance of cellular redox homeostasis, epigenetic regulation and environmental fitness. The widespread presence of dnd systems is considered a consequence of extensive horizontal gene transfer, whereas the lability of PT during oxidative stress and the susceptibility of PT to PT-dependent endonucleases provide possible explanations for the ubiquitous but sporadic distribution of PT modification in the bacterial world.
-
5.
DNA Methylation Status in Cancer Disease: Modulations by Plant-Derived Natural Compounds and Dietary Interventions.
Jasek, K, Kubatka, P, Samec, M, Liskova, A, Smejkal, K, Vybohova, D, Bugos, O, Biskupska-Bodova, K, Bielik, T, Zubor, P, et al
Biomolecules. 2019;(7)
Abstract
The modulation of the activity of DNA methyltransferases (DNMTs) represents a crucial epigenetic mechanism affecting gene expressions or DNA repair mechanisms in the cells. Aberrant modifications in the function of DNMTs are a fundamental event and part of the pathogenesis of human cancer. Phytochemicals, which are biosynthesized in plants in the form of secondary metabolites, represent an important source of biomolecules with pleiotropic effects and thus provide a wide range of possible clinical applications. It is well documented that phytochemicals demonstrate significant anticancer properties, and in this regard, rapid development within preclinical research is encouraging. Phytochemicals affect several epigenetic molecular mechanisms, including DNA methylation patterns such as the hypermethylation of tumor-suppressor genes and the global hypomethylation of oncogenes, that are specific cellular signs of cancer development and progression. This review will focus on the latest achievements in using plant-derived compounds and plant-based diets targeting epigenetic regulators and modulators of gene transcription in preclinical and clinical research in order to generate novel anticancer drugs as sensitizers for conventional therapy or compounds suitable for the chemoprevention clinical setting in at-risk individuals. In conclusion, indisputable anticancer activities of dietary phytochemicals linked with proper regulation of DNA methylation status have been described. However, precisely designed and well-controlled clinical studies are needed to confirm their beneficial epigenetic effects after long-term consumption in humans.
-
6.
Role of histone modification and DNA methylation in signaling pathways involved in diabetic retinopathy.
Shafabakhsh, R, Aghadavod, E, Ghayour-Mobarhan, M, Ferns, G, Asemi, Z
Journal of cellular physiology. 2019;(6):7839-7846
Abstract
Retinopathy, characterized by an alteration of the retinal microvasculature, is a common complication of diabetes mellitus. These changes can cause increased permeability and alter endothelial cell proliferation, edema, and abnormal neovascularization and eventually result in blindness. The pathogenesis of diabetic retinopathy (DR) is complicated, involving many factors/mediators such as genetic susceptibility, microRNAs, and cytokines. One of the factors involved in DR pathogenesis is epigenetic changes that can have a key role in the regulation of gene expression; these include microRNAs, histone modifications, and methylation of DNA. The main epigenetic modifications are DNA methylation and posttranslational modifications of the histones. Generally, the studies on epigenetics can provide new opportunities to investigate the molecular basis of diseases with complicated pathogenesis, including DR, and provide essential insights into the potential design of strategies for its treatment. The aim of this study is an investigation of DR pathogenesis and epigenetic modifications that involve in DR development.
-
7.
Epigenetic Targets for Therapeutic Approaches in COPD and Asthma. Nutrigenomics – Possible or Illusive.
Cherneva, RV, Kostadinov, D
Folia medica. 2019;(3):358-369
Abstract
Oxidative stress generated by cigarette smoking, environmental pollution, or other noxious particles leads to epigenetic changes in the cells of the respiratory tract. They reflect cell adaptation in response to chronic exposure to external factors. Although there is no change in the genetic code, epigenetic changes may be heritable and translated from one generation to another, accumulating abnormalities and rendering cells into entirely different phenotype, causing disease. DNA methylation, post-translation histone modification, ubiquitination, sumoylation and miRNA transcriptional regulation are the major processes that are responsible for the epigenetic control of gene expression. All of them are reversible. They can be regulated by targeting specific enzymes/proteins involved in the process in order to mitigate inflammation. Chronic respiratory diseases have epigenetic signatures that affect gene expression in the lung. Targeting them provides the development of novel diagnostic and therapeutic approaches in respiratory medicine. Nutrigenomics reveals the beneficial effect of natural phytochemicals, affecting key steps in the signaling pathways of chronic respiratory diseases.
-
8.
Impact of sex differences and gender specificity on behavioral characteristics and pathophysiology of neurodegenerative disorders.
Ullah, MF, Ahmad, A, Bhat, SH, Abu-Duhier, FM, Barreto, GE, Ashraf, GM
Neuroscience and biobehavioral reviews. 2019;:95-105
Abstract
The impact of neurodegenerative disorders in humans has multiple consequences because of the progressive decline in cognitive and physical performances. These disorders have diverse manifestations and are influenced by genetic and lifestyle factors, concurrent health conditions as well as un-modifiable predisposing risk factors, including gender and advanced age. Accumulating evidence indicates a gender-dependent natural bias of neurodegenerative diseases, such as, Alzheimer's disease, Parkinson's disease, Huntington's disease and multiple sclerosis, with the ratio of male to female prevalence as well as the severity of the disease differing significantly between the two sexes. This observation has recently garnered much attention and it is now being realized that understanding the sex as a biological variable in the etiology of the neurodegenerative diseases may advance the status of the pathophysiology and treatment strategies while improving the associated decline in cognitive and functional abilities. This review highlights the influence of gender in neurodegenerative disorders and further discusses the sex-specific pre-determined microenvironments that are critical in predisposing the individuals to such disorders.
-
9.
Slowing Down Ageing: The Role of Nutrients and Microbiota in Modulation of the Epigenome.
Gadecka, A, Bielak-Zmijewska, A
Nutrients. 2019;(6)
Abstract
The human population is getting ageing. Both ageing and age-related diseases are correlated with an increased number of senescent cells in the organism. Senescent cells do not divide but are metabolically active and influence their environment by secreting many proteins due to a phenomenon known as senescence associated secretory phenotype (SASP). Senescent cells differ from young cells by several features. They possess more damaged DNA, more impaired mitochondria and an increased level of free radicals that cause the oxidation of macromolecules. However, not only biochemical and structural changes are related to senescence. Senescent cells have an altered chromatin structure, and in consequence, altered gene expression. With age, the level of heterochromatin decreases, and less condensed chromatin is more prone to DNA damage. On the one hand, some gene promoters are easily available for the transcriptional machinery; on the other hand, some genes are more protected (locally increased level of heterochromatin). The structure of chromatin is precisely regulated by the epigenetic modification of DNA and posttranslational modification of histones. The methylation of DNA inhibits transcription, histone methylation mostly leads to a more condensed chromatin structure (with some exceptions) and acetylation plays an opposing role. The modification of both DNA and histones is regulated by factors present in the diet. This means that compounds contained in daily food can alter gene expression and protect cells from senescence, and therefore protect the organism from ageing. An opinion prevailed for some time that compounds from the diet do not act through direct regulation of the processes in the organism but through modification of the physiology of the microbiome. In this review we try to explain the role of some food compounds, which by acting on the epigenetic level might protect the organism from age-related diseases and slow down ageing. We also try to shed some light on the role of microbiome in this process.
-
10.
New Promises to Cure Cancer and Other Genetic Diseases/Disorders: Epi-drugs Through Epigenetics.
Duan, YT, Sangani, CB, Liu, W, Soni, KV, Yao, Y
Current topics in medicinal chemistry. 2019;(12):972-994
Abstract
All the heritable alterations in gene expression and chromatin structure due to chemical modifications that do not involve changes in the primary gene nucleotide sequence are referred to as epigenetics. DNA methylation, histone modifications, and non-coding RNAs are distinct types of epigenetic inheritance. Epigenetic patterns have been linked to the developmental stages, environmental exposure, and diet. Therapeutic strategies are now being developed to target human diseases such as cancer with mutations in epigenetic regulatory genes using specific inhibitors. Within the past two decades, seven epigenetic drugs have received regulatory approval and many others show their candidature in clinical trials. The current article represents a review of epigenetic heritance, diseases connected with epigenetic alterations and regulatory approved epigenetic drugs as future medicines.