Fetal origins of insulin resistance and the metabolic syndrome: A key role for adipose tissue?

For several years now, the epidemiolopical data have shown an inverse relationship between birth-weight and the development in later life of cardiovascular disease and metabolic disorders. The term small for gestational age (SGA) describes a neonate whose birth-weight is two standard deviations (SD) below the reference mean, corrected for gestational age and gender, SGA is associated with increased risks of developing hypertension, insulin resistance and type 2 diabetes. Howefer, the association with an atherogenic lipid profile is less clear. Nevertheless, all of the components of the metabolic syndrome are pressent. Yet, in spite of the large body of data in the literature, the biological mechanisms underlying this association are still unclear. To explain the association, various hypotheses have been proposed, pointing to the role of detrimental fetal environment or genetic suspectibility, or interaction between the two, and to the particular dynamic changes in adiposity that occur during catch-up growth. However, not only quantitative, but also qualitative, abnormalities of adipose tissue have been observed, suggesting a critical role of this organ in this development of metabolic complications. (C) 2009 Published by Elsevier Masson SAS.