Foetal adipose tissue fatty acid accretion - abstract

ABSTRACT

There are still uncertainties about the origin of the fatty acids (FA) deposited in the foetus, notably the percentage derived from the maternal circulation. This study describes a method to determine the amount of FA synthesized de novo in the foetus and the amount derived from the maternal circulation. Autopsy samples of subcutaeneous adipose tissue were obtained from 42 black foetuses and newborn infants. Samples of similar tissue were obtained from 50 pregnant women and 13 non-pregnant black women during surgery. FA analysis was done by gas chromatography. The accretion rate of FA in foetal adipose tissue was calculated by linear regression analysis of the FA data obtained from foetal/infant samples from the 22nd to 43rd week of gestation. The rate of foetal FA synthesized de novo in adipose tissue was calculated as the difference between the total foetal FA accretion rate and an estimate of the maternally derived FA. The latter was estimated from the values for accretion rates of saturated FA (SAFA), mono-unsaturated FA (MUFA), and polyunsaturated FA (PUFA) and total FA in foetal tissue, and the SAFA, MUFA and PUFA composition of adipose tissue in women (Table). Results show that of the total FA increment in foetal adipose tissue (22.7mg/g wet wt./week), 86.6 per cent was synthesized de novo by the foetus and the rest (13.2 per cent) was maternally derived (AU)