For a study, researchers wanted to see if shielding parenteral feeding solutions from light and supplementing them with N-acetylcysteine (NAC) improves mesenteric blood flow, gut shape, and oxidative state in parenterally fed neonates. The superior mesenteric artery was surgically equipped with central venous catheters and an ultrasonic blood flow sensor in neonatal Yucatan miniature pigs (n = 23, 7–11 days old). Piglets were given either light-protected (LP) or light-exposed (LE) full parenteral nutrition enhanced with NAC or alanine continuously for 7 days (ALA).

After 7 days, there were no variations in body weight or overall gut morphology between groups. On day 7, plasma NAC concentrations (N-acetylcysteine: 94 vs 7 μmol/L; P < 0.001; homocysteine: 14 versus 21 μmol/L; P < 0.005) were higher and total homocysteine was lower in NAC-supplemented pigs compared to ALA-supplemented pigs; plasma total glutathione was unaffected. In pigs given LP parenteral feeding (P < 0.05), hepatic lipid peroxidation was decreased by 25%. Parenteral feeding reduced mesenteric artery blood flow in all pigs between days 2 and 6 (P < 0.001). When compared to LE-ALA (37%; P < 0.05) and LP-NAC pigs (43%; P = 0.062), photoprotection alone (LP-ALA) reduced mesenteric blood flow to 66% of baseline on day 6; LE-NAC piglets experienced intermediate reductions of about 55% in blood flow. Photoprotection of parenteral nutrition solutions is a simple and efficient way to reduce the drop in blood flow to the stomach and hepatic lipid peroxidation, both of which are major side effects of parenteral feeding.