FIG. 7.

Roles of macro- and micro-nutrients in epigenetics and physiological responses. Nutrients, particularly amino acids, regulate cellular redox state, the secretion of hormones (e.g., insulin and insulin-like growth factors), physiological functions, and whole-body homeostasis in humans and animals through three mechanisms: (1) the expression of genes; (2) the production of signaling gases and other metabolites; and (3) MTOR activation. S-Adenosylmethionine is the major methyl group donor in cells and its synthesis is affected by amino acids (e.g., methionine, serine, glycine, and histidine), B vitamins (including folate, vitamin B₁₂, and vitamin B₆), choline, and creatine. Methylation of DNA and protein contributes to epigenetics, which results in transcriptional activation or inhibition of select genes. Changes in intracellular protein turnover (protein synthesis and degradation) and protein kinase cascades can alter physiological responses in the fetus and offspring. CO, carbon monoxide; 4EBP1, eIF4E-binding protein-1; GH, growth hormone; H₂S, hydrogen sulfide; IGF, insulin-like growth factor; MTOR, mechanistic target of rapamycin; NO, nitric oxide; SAM, S-adenosylmethionine; S6K1, ribosomal protein S6 kinase-1; SPP1, secreted phosphoprotein 1.