Epigenetics of undernutrition

Abstract

The term undernutrition commonly refers to underfeeding and poor nutritional status. This condition is primarily caused by an inadequate intake of dietary energy or some specific nutrients, which accompany starvation or famine, voluntary reduction of food intake, gastrointestinal disorders, parasitic infestations, and severe pathologies that result in enhanced tissue catabolism. Of special importance is undernutrition during gestation (unbalanced maternal diet or intrauterine growth retardation) and lactation, as it compromises in- utero development and impairs infant growth and neurocognitive functions. Moreover, undernutrition is related to immunodeficiency, accelerated aging, and has potential deleterious consequences for adult health, including neurological disorders, cardiovascular diseases, obesity, diabetes, and cancer. Cumulative evidence has demonstrated that diverse environmental factors, including undernutrition, can modify epigenetic marks (particularly DNA methylation, covalent histone modifications, and noncoding RNAs) throughout life, affecting gene expression and cell function, with long-term effects on health in adult life. Of particular interest is the impact of undernutrition on the epigenome driven by the lack of dietary methyl donors (choline, betaine, folate, and vitamins B2, B6, and B12) and other micronutrients, low-protein diets, calorie restriction, and famine exposure. This knowledge is contributing to a better understanding of the role of dietary deficiencies in the development of several adverse conditions through epigenetic mechanisms. Moreover, these scientific insights are leading to design novel dietary interventions targeting the epigenome.