Contexto, ser humano y epigenética / Context, human being and epigenetics

RESUMEN

Resumen Los últimos años de investigación científica han visto un crecimiento en los estudios que relacionan situaciones de vulnerabilidad (particularmente, durante la vida temprana) con el desarrollo de psicopatologías. Tales disfuncionalidades en la salud mental y en las emociones entienden una sinergia entre factores contextuales y la biología del organismo. Lo que da en llamarse "puente" entre ambas instancias es estudiado por un área de la investigación científica relativamente nueva la epigenética. La epigenética fue establecida como un interesante factor que permite relacionar, desde un punto de vista biológico, el contexto en que se desarrollan las personas con sus estados emocionales. Este artículo se propone revisar algunos trabajos e integrarlos dentro de una concepción compleja del ser humano, que lo entiende como un sistema de relaciones entre diversas dimensiones que incluyen las esferas genéticas, epigenéticas, neurológicas, emocionales, interaccionales, cognitivas y socioculturales enmarcadas en un contexto particular.

ABSTRACT

Abstract The discovery of the whole sequence of the human genome in 2001 promised to be a revolution in terms of dealing with diseases and understanding what makes us a "different" species from other animals. However, the scope of this promising discovery was more limited than expected. The information carried by DNA is complex and, furthermore, it does not explain the vast repertoire of functions and dysfunctions that organisms present. For this reason, it began to be thought that it was necessary to change the focus to understand how individuals are formed and develop, and turn the attention paid to DNA to what surrounds that DNA the environment of the organism (both internal and external). In this way, the studies began to focus on the influence of the context to which organisms are exposed to understand the characteristics of the body and its actions. In thinking about the concept of the body in development, this renewed focus in the environmental influence allows an understanding of it as a permeable and complex system, where dysregulations (diseases) may also be triggered by exogenous events and not only from the endogenous factors. Therefore, in a recursive way, the influence of the human being on the environment transforms the environment that returns to influence the human being. Here is the history of mankind. There are contexts that offer a healthy framework for the growth of its inhabitants and there are others that make life vulnerable and produce lifetime consequences. However, while some people are and feel vulnerable to contexts of adversity, other people are resilient and manage to positively live and growth despite the difficulties that might appear throughout life. Epigenetics has been proposed as one of the molecular mechanisms that explain how those contexts "get under the skin" and trigger phenotypic characteristics. Although the regulation of gene expression by epigenetic mechanisms occurs naturally and constantly in the developing organism, it can also be influenced by environmental factors, such as age, lifestyle, health conditions or social relationships. Epigenetics is sensitive to environmental changes allowing organisms to adapt their physiology and behavior. Unlike the changes that occur in the DNA sequence, epigenetic processes are reversible. One of the most known examples of epigenetic action in determining phenotypes according to the environment is the stress response through the hypothalamus-pituitary-adrenal (HPA) axis. The functioning of the HPA axis and the response to stress can be related to the concepts of vulnerability and trauma. If an emotionally sensitive event is disturbing, it becomes a stressful situation, with the activation of the HPA axis, flooding the bloodstream with cortisol. This allostatic process is the basis of the mechanism of adaptability of humans to traumatic impacts. But if the situation continues to impact, allostasis is systematized and generates an allostatic circuit that produces a residual charge that ends up creating dysfunction in the organism. In this article the involvement of epigenetics in this regulation is discussed and some seminal studies in rodents and humans are presented. The last few years of scientific research have seen an explosive growth of studies linking situations of vulnerability (particularly, during early life) with the development of psychopathologies. Epigenetics was established as an interesting factor that allows to relate, from a biological point of view, the context in which people develop with their emotional states. This article proposes a review of some of these works in order to integrate them into a complex conception of the human being, which understands it as a system of relationships between various dimensions, including genetics, epigenetics, neurology, emotions, social interactions, cognition, and socio-culture, framed in a particular context.