Long term effects of pre- and early postnatal nutrition and environment on the gut.

The Developmental Origins of Health and Disease hypothesis formulated in the early 1990 s has stimulated research on long-term effects of early nutrition and environment over the last decades. Long-term is understood in this review as physiologically relevant periods such as after weaning, around sexual maturity, and in adulthood, as opposed to early developmental periods. The small and large intestines as targets for the study of long-term effects have received little attention until recent years and the stomach has been considered very rarely. Data have accumulated for laboratory animal models but they are still scarce in the swine species. Following the epidemics of metabolic diseases and obesity in western countries, experimental evidence has been published showing that nutritional factors, including energy, fat and fatty acids, protein, and micronutrients impact various facets of gut function. These include alterations in intestinal digestive, absorptive, secretory, barrier, and defense systems, often in a way potentially detrimental to the host. Environmental factors with long-term influence include stress (e.g., maternal deprivation, neonatal gut irritation), chemical pollutants (e.g., bisphenol A), and gut microbiota disturbances (e.g., by antibiotics). Examples of such long-term effects on the gut are provided in both laboratory animals and pigs together with underlying physiological mechanisms whenever available. Experimental evidence for the involvement of underlying epigenetic modifications (e.g., genomic DNA methylation) in long-term studies has just started to emerge with regard to the gastrointestinal tract. Also, interactions between the microbiota and the host are being considered pivotal in the early programming of gut functions. Finally, suggestions for future research are provided in order to better understand and then control early programming as an attempt to optimize vital functions of the gastrointestinal tract throughout adult life.