Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states

Epigenetic signatures are heritable changes that can alter gene expression without modifying the DNA sequence. One major epigenetic mechanism is the methylation of CpG sites, which involves the incorporation of a methyl group into a cytosine that is adjacent to a guanine. DNA methylation patterns ca...

Full description

Bibliographic Details
Main Authors: Arpon, A. (Ana), Martinez, J.A. (José Alfredo), Riezu-Boj, J.I. (José Ignacio)
Format: info:eu-repo/semantics/doctoralThesis
Language:eng
Published: 2019
Subjects:
Online Access:https://hdl.handle.net/10171/58456
_version_ 1793400529592778752
author Arpon, A. (Ana)
Martinez, J.A. (José Alfredo)
Riezu-Boj, J.I. (José Ignacio)
author_facet Arpon, A. (Ana)
Martinez, J.A. (José Alfredo)
Riezu-Boj, J.I. (José Ignacio)
author_sort Arpon, A. (Ana)
collection DSpace
description Epigenetic signatures are heritable changes that can alter gene expression without modifying the DNA sequence. One major epigenetic mechanism is the methylation of CpG sites, which involves the incorporation of a methyl group into a cytosine that is adjacent to a guanine. DNA methylation patterns can be influenced by environmental factors and can change stochastically as a result of ageing, and thereby, modulate gene expression. Modifications in DNA methylation marks can alter the susceptibility to certain diseases and health impairments, including neurological disorders, obesity, type 2 diabetes and cardiovascular disease. In this context, DNA methylation alterations have emerged as promising biomarkers for disease screening, detection, and prediction, in addition to being potential targets for the development of new therapeutic approaches. Thus, the general objective of the current research is to identify DNA methylation patterns associated with different physiological, metabolic and nutritional states that might contribute to the development of biomarker panels and potential therapeutic targets. In order to achieve this, epigenome-wide association studies were performed in different populations to determine candidate CpG sites related to factors and features that could influence and/or be associated with DNA methylation. These included prematurity, a Mediterranean diet, insulin sensitivity and resistance, abdominal obesity and epigenetic age. Altogether, the results of the current thesis demonstrate that alterations in DNA methylation marks depend on the screened physiological, metabolic and nutritional state of the individual. Due to the plasticity of the epigenetic system, environmental factors can influence DNA methylation signatures, both during the first stages of life and during the adulthood. As such, prematurity and nutrition are two determinant factors of DNA methylation levels. The findings of this investigation revealed that preterm newborns exhibit lower levels of methylation of a CpG located at the SLC6A3 gene, which is related to neurodevelopment. Regarding nutrition, following a Mediterranean diet was associated with alterations in the methylation of genes related to inflammatory and metabolic pathways, where fat quality may also play a role. Moreover, some DNA methylation signatures were associated with insulin sensitivity, insulin resistance and abdominal adiposity, supporting an influence of epigenetics on metabolic pathways and in the onset and progression of metabolic diseases. For instance, LPL and CTNND2 were highly associated with insulin sensitivity, able to accurately discern between subjects with low and high insulin sensitivity values. Concerning insulin resistance, four CpGs located at genes involved in glucose- and insulin-related pathways, including the SH3RF3 and MAN2C1 genes, were capable of distinguishing low and high insulin resistance levels. On the other hand, differential DNA methylation values were also found for subjects with and without central obesity, which could be discriminated by four CpGs in women (c13orf36, ZC3H12D, MYO9B, KCNG3) and one in men (TCP11L1). Lastly, ageing was also related to changes in DNA methylation, confirming that an unhealthy metabolic state accelerates the epigenetic age, possibly leading to early health deterioration. Overall, this research provides new insights into the underlying epigenetic mechanisms associated with prematurity, metabolic diseases and ageing, suggesting different CpG sites as putative biomarkers for diagnosis and prognosis or as potential therapeutic targets for the prevention and treatment of chronic diseases.
format info:eu-repo/semantics/doctoralThesis
id oai:dadun.unav.edu:10171-58456
institution Universidad de Navarra
language eng
publishDate 2019
record_format dspace
spelling oai:dadun.unav.edu:10171-584562020-07-21T01:01:25Z Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states Arpon, A. (Ana) Martinez, J.A. (José Alfredo) Riezu-Boj, J.I. (José Ignacio) Genética humana Metabolismo humano Enfermedades de la nutrición Materias Investigacion::Ciencias de la Salud::Genética Epigenetic signatures are heritable changes that can alter gene expression without modifying the DNA sequence. One major epigenetic mechanism is the methylation of CpG sites, which involves the incorporation of a methyl group into a cytosine that is adjacent to a guanine. DNA methylation patterns can be influenced by environmental factors and can change stochastically as a result of ageing, and thereby, modulate gene expression. Modifications in DNA methylation marks can alter the susceptibility to certain diseases and health impairments, including neurological disorders, obesity, type 2 diabetes and cardiovascular disease. In this context, DNA methylation alterations have emerged as promising biomarkers for disease screening, detection, and prediction, in addition to being potential targets for the development of new therapeutic approaches. Thus, the general objective of the current research is to identify DNA methylation patterns associated with different physiological, metabolic and nutritional states that might contribute to the development of biomarker panels and potential therapeutic targets. In order to achieve this, epigenome-wide association studies were performed in different populations to determine candidate CpG sites related to factors and features that could influence and/or be associated with DNA methylation. These included prematurity, a Mediterranean diet, insulin sensitivity and resistance, abdominal obesity and epigenetic age. Altogether, the results of the current thesis demonstrate that alterations in DNA methylation marks depend on the screened physiological, metabolic and nutritional state of the individual. Due to the plasticity of the epigenetic system, environmental factors can influence DNA methylation signatures, both during the first stages of life and during the adulthood. As such, prematurity and nutrition are two determinant factors of DNA methylation levels. The findings of this investigation revealed that preterm newborns exhibit lower levels of methylation of a CpG located at the SLC6A3 gene, which is related to neurodevelopment. Regarding nutrition, following a Mediterranean diet was associated with alterations in the methylation of genes related to inflammatory and metabolic pathways, where fat quality may also play a role. Moreover, some DNA methylation signatures were associated with insulin sensitivity, insulin resistance and abdominal adiposity, supporting an influence of epigenetics on metabolic pathways and in the onset and progression of metabolic diseases. For instance, LPL and CTNND2 were highly associated with insulin sensitivity, able to accurately discern between subjects with low and high insulin sensitivity values. Concerning insulin resistance, four CpGs located at genes involved in glucose- and insulin-related pathways, including the SH3RF3 and MAN2C1 genes, were capable of distinguishing low and high insulin resistance levels. On the other hand, differential DNA methylation values were also found for subjects with and without central obesity, which could be discriminated by four CpGs in women (c13orf36, ZC3H12D, MYO9B, KCNG3) and one in men (TCP11L1). Lastly, ageing was also related to changes in DNA methylation, confirming that an unhealthy metabolic state accelerates the epigenetic age, possibly leading to early health deterioration. Overall, this research provides new insights into the underlying epigenetic mechanisms associated with prematurity, metabolic diseases and ageing, suggesting different CpG sites as putative biomarkers for diagnosis and prognosis or as potential therapeutic targets for the prevention and treatment of chronic diseases. 2019-11-07T12:33:52Z 2019-11-07T12:33:52Z 2019-11-07 2019-10-10 info:eu-repo/semantics/doctoralThesis https://hdl.handle.net/10171/58456 eng info:eu-repo/semantics/openAccess application/pdf
spellingShingle Genética humana
Metabolismo humano
Enfermedades de la nutrición
Materias Investigacion::Ciencias de la Salud::Genética
Arpon, A. (Ana)
Martinez, J.A. (José Alfredo)
Riezu-Boj, J.I. (José Ignacio)
Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title_full Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title_fullStr Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title_full_unstemmed Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title_short Epigenetic DNA methylation signatures in different physiological, metabolic and nutritional states
title_sort epigenetic dna methylation signatures in different physiological, metabolic and nutritional states
topic Genética humana
Metabolismo humano
Enfermedades de la nutrición
Materias Investigacion::Ciencias de la Salud::Genética
url https://hdl.handle.net/10171/58456
work_keys_str_mv AT arponaana epigeneticdnamethylationsignaturesindifferentphysiologicalmetabolicandnutritionalstates
AT martinezjajosealfredo epigeneticdnamethylationsignaturesindifferentphysiologicalmetabolicandnutritionalstates
AT riezubojjijoseignacio epigeneticdnamethylationsignaturesindifferentphysiologicalmetabolicandnutritionalstates