The influence of dietary nucleotides on erythrocyte membrane fatty acids and plasma lipids in preterm infants

OBJECTIVE: The objective of this study was to evaluate whether a regular formula for premature infants supplemented with nucleotides has any influence on plasma lipids and erythrocyte membrane fatty acids. METHODS: Preterm infants fed either human milk supplemented with human milk protein (HM, n = 14), nucleotide-supplemented preterm formula (NF, n = 13), or a regular preterm formula (F, n = 13) were included in the study. The NF was supplemented with 18.2 mg cytidine monophosphate/l (CMP), 7.0 mg uridine monophosphate/l (UMP), 6.4 mg adenosine monophosphate/l (AMP), 3.0 mg inosine monophosphate/l (IMP) and 3.0 mg guanosine monophosphate/l (GMP). RESULTS: There were significantly higher concentrations of triglycerides (TG) in infants fed NF compared to those fed F (191.42 +/- 79.58 vs 108.21 +/- 43.73, p < 0.001, mean +/- SD lipid concentrations, mg/100 ml plasma). Infants fed F had significantly lower concentrations of total cholesterol (94.34 +/- 11.71 vs 115.69 +/- 39.29, p < 0.01) and TG in plasma (108.21 +/- 43.73 vs 172.27 +/- 68.19, p < 0.001, mean +/- SD lipid concentrations, mg/100 ml plasma) when compared to HM-fed infants. There were no significant differences in any of the erythrocyte membrane fatty acids and total long-chain polyunsaturated fatty acids (LC-PUFA) between NF and F during the study period (6 weeks). Furthermore, total LC-PUFA and docosahexaenoic acid (DHA) concentrations in red blood cell were not significantly different when infants fed NF were compared to those fed HM. In contrast, however, infants fed F had significantly lower concentrations of total n-3 LC-PUFA (p < 0.01) and DHA (p < 0.01) than those found in HM-fed infants. CONCLUSIONS: These results do not suggest an effect of nucleotides on the red blood cell LC-PUFA profile in preterm infants. However, the nucleotides may increase the concentrations of triglycerides in plasma