Epigenetic changes caused by intrauterine malnutrition as potential disease mediator and early prevention in developmental stages

Presently, the incidences of noncommunicable diseases (NCD) have been increasing in both low- and middle-income countries worldwidely. Effective long-term and multigeneration interventions to decrease the risk of NCD should be developed and introduced. The environment in utero alters phenotypes mainly through epigenetic mechanisms. The epigenetic changes induced in an unfavorable developmental environment have lifelong effects on cardiovascular and metabolic functions, susceptibility to cardiovascular disease, obesity, and other NCD. Although compared with animals, epigenetic analysis of human specimens is restricted except for peripheral blood, placental, or umbilical specimens, recently, important human studies have been reported concerning the epigenetic analysis of Line 1 gene from the umbilical blood, umbilical RXRα, or the peripheral nuclear cell IGF-2. The birth weight is an indirect marker of in-the-womb nutritional status. The incidence of low-birth-weight infants, weighing less than 2,500 g, has been increasing in Japan. Presently, it is higher than that in the latter half of the 20 s of the Showa era, and is the highest among the OECD countries. This trend suggests that in Japan the intrauterine nutritional status has been deteriorating. We have to change this trend and put much attention on the prepregnancy and pregnancy nutrition for the present and future generations.