PARENTERAL FEEDING OF PRETERM INFANTS WITH TWO FAT EMULSIONS CONTAINING LONG AND MEDIUM CHAIN TRIGLYCERIDES: EVALUATION OF OXIDATIVE STRESS

Abstract

Background: Polyunsaturated fatty acid (PUFA), a major component of fat emulsions, are susceptible to peroxidation. Total hydroperoxides (TH), which are the intermediate oxidative products of lipids, peptides, and amino acids, represent a measure of overall oxidative stress. Advanced oxidation protein products (AOPP) are reliable markers of the degree of protein damage in oxidative stress. Premature infants have limited ability to cope with oxidative stress. Aim: To evaluate the oxidative effects of short-term total parenteral nutrition (TPN) with two lipid emulsions (soybean and coconut oil-based ) in premature infants. Methods: In a double blind randomised trial, 12 preterm infants received either a standard soybean oil or a coconut oil emulsion. Lipid intake represented 20-25% of the total non-protein energy daily intake. Infants were included with gestational age from 28 to 36 weeks and birth weight > 500 g. All babies studied did not have blood group incompability, infections, hypoxia and severe hyperbilirubinaemia. At baseline and after 7 days we measured plasma levels of (TH) and (AOPP). The procedure used has been reported by G. Buonocore et al. (Pediatric Reasearch, 2000). The data (expressed as means +/− SD) were analyzed for statistically significant differences by two-tailed t test for unpaired data (SPSS/PC). Results: 12 preterm infants (mean gestational age 32 weeks, mean birth weight 1150 g), were randomized to receive soybean oil-based emulsion (6 babies): LCT group and coconut oil-based emulsion (6 babies): MCT group. Conclusion: The significantly high TH plasma levels found in preterm babies fed with the soybean oil emulsion (LCT group) are an indirect evidence of an increase in generation of free radicals (FR). The AOPP plasma levels did not significantly differ at T0 and T7, indicating low protein damage, as AOPP have been described as markers of protein oxidative stress. Therefore, the generation of FR exposes the premature infants, with a poorly developed antioxidant system, mainly to a lipid damage. A partial replacement of PUFA by MCT in fat emulsion could have a favourable influence on adverse effects caused by FR, which are generated by lipid peroxidation.TABLE 1: Shows data related to TH (Carr U/L) are showedTABLE 2: Shows the data related to AOPP (Umol/dl)