Alterations in Reserve Bilirubin Binding Capacity of Albumin by Free Fatty Acids. II. In Vitro and In Vivo Studies Using Difference Spectroscopy

Whitington, Peter F.; Burckart, Gilbert J.; Gross, Sharon; Korones, Sheldon B.; Helms, Richard A.

doi:10.1097/00005176-198212000-00009

Cited by 11 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…8 The relationship between F/A ratio and the binding of bilirubin to albumin has been evaluated by several investigators. 4,6,25,26 Spear et al 10 reported linear correlation between B f concentration and F/A ratio, with infants who had an F/A ratio of >4:1 having the largest increase in B f . Because FFA was not measured in our study, we were not able to evaluate the relationship between F/A ratio and bilirubin-albumin binding variables as a function of IL intake and GA.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Intravenous Lipid and Bilirubin-Albumin Binding Variables in Premature Infants

et al. 2009

View full text Add to dashboard Cite

BACKGROUND The lipid intake at which a significant bilirubin-displacing effect occurs as a function of gestational age (GA) is unclear. OBJECTIVE To determine the effect of gradual increase in IL intake from 1.5 to 3 g/kg per day on bilirubin-albumin binding variables as a function of GA in premature infants with indirect hyperbilirubinemia. METHODS Infants of 24 to 33 weeks’ gestation at birth who received IL (20% Intralipid [Fresenius Kabi, Uppsala, Sweden]) doses of 1.5, 2, 2.5, and 3 g/kg per day over 4 consecutive days were prospectively evaluated. The blood samples were drawn twice at least 8 hours apart on each IL intake to measure total serum bilirubin and free bilirubin by the peroxidase test. The highest free bilirubin on each IL intake, the corresponding total serum bilirubin, and serum albumin were used to calculate the bilirubin/albumin binding constant or binding affinity. RESULTS Sixty-two infants (median GA: 28 weeks) were studied during the first 10 days of life. None of the subjects had culture-proven sepsis, had triglyceride levels of >2.05 mmol/L, or were receiving steroids. Infants were grouped in 2-week GA intervals. The cumulative frequency of elevated free bilirubin concentration (≥90th percentile or Bf ≥ 32 nmol/L) as a function of IL intake was inversely related to GA and was significantly different among 2-week GA groups. There was significant decrease in binding affinity and increase in free bilirubin concentration with higher IL intake for ≤28 week but not for >28 week GA groups. CONCLUSIONS The IL intake may be associated with a significant fall in the binding affinity of bilirubin for plasma protein and a concomitant increase in free bilirubin concentration in premature infants. The lipid intake at which this occurs depends on GA.

show abstract

Section: Discussionmentioning

confidence: 99%

“…1–3 The elevated FFA concentration may displace bilirubin from albumin-binding sites, increasing free or unbound bilirubin (B f , bilirubin not bound to albumin) concentration. 1,4–6 B f crosses the intact blood-brain barrier and may cause brain injury, according to the current theory on the pathogenesis of bilirubin-induced neurotoxicity. 7–9 …”

mentioning

confidence: 99%

Intravenous Lipid and Bilirubin-Albumin Binding Variables in Premature Infants

et al. 2009

View full text Add to dashboard Cite

show abstract

“…The relationship between FFA and the binding of bilirubin to albumin has been evaluated by several investigators 3 . ‐ 5 , 14 , 30 ‐ 32 FFA binds to albumin at 3 sites. The third binding site of FFA is also the highest affinity binding site of bilirubin to albumin.…”

Section: Discussionmentioning

confidence: 99%

“…Several factors may influence bilirubin–albumin binding affinity, including elevated free fatty acid (FFA) concentrations 1 , 3 . ‐ 5 Intravenous lipid emulsion (IL), commonly used to provide a concentrated isotonic source of calories during the first few weeks of postnatal life, may be associated with elevated FFA concentration in premature infants because premature infants clear FFA less effectively than term infants 6 . ‐ 8 …”

mentioning

confidence: 99%

Effect of Free Fatty Acids on Bilirubin–Albumin Binding Affinity and Unbound Bilirubin in Premature Infants

Amin

2010

J Parenter Enteral Nutr

View full text Add to dashboard Cite

Background The author has previously shown that intravenous lipid intake may be associated with an increase in unbound bilirubin in infants ≤28 weeks gestational age. The objective of this study was to evaluate whether this increase in unbound bilirubin is mediated by free fatty acids and to examine the secondary effect of free fatty acids on bilirubin–albumin binding affinity. Methods A prospective study was conducted to include 26 infants ≤32 weeks gestational age with indirect hyperbilirubinemia and receiving intravenous lipids during the first 10 postnatal days. Blood samples were collected for unbound bilirubin, binding affinity, and free fatty acid measurement at varying intravenous lipid intakes (1–3 g/kg/d). Regression analyses were performed to evaluate the roles of free fatty acids and binding affinity as mediators. Results Intravenous lipid intake was significantly associated with an increase in free fatty acids and unbound bilirubin in infants ≤28 weeks but not >28 weeks gestational age. In infants ≤28 weeks gestational age, each unit increase in free fatty acids was significantly associated with a decrease in binding affinity, which was significantly associated with an increase in unbound bilirubin. Conclusions In infants ≤28 weeks gestational age, intravenous lipid intake may be associated with an increase in unbound bilirubin, and this is mediated by an increase in free fatty acids and a secondary decrease in binding affinity. In infants >28 weeks gestational age, higher intravenous lipid intake may be used because it is unassociated with increases in free fatty acids and unbound bilirubin.

show abstract

“…31,32 Although the impact of endogenous FFA has not been assessed directly, increased FFA has bilirubin displacing effects, especially in premature newborns receiving intravenous lipid supplementation for nutrition and growth. 7,9,10,28,33 At an FFA/Alb ratio 54, FFAs compete with bilirubin at the bilirubin binding site, resulting in the displacement of bilirubin. 7,8,10,27,28 We found that endogenous FFAs did not affect Alb binding of bilirubin, resulting in elevations of UB, since none of the sera, from both term and preterm infants, had FFA/Alb ratios 54.…”

Section: Discussionmentioning

confidence: 99%

Postnatal serum concentrations of endogenous free fatty acids in newborns admitted to the neonatal intensive care unit: effects on unbound bilirubin

et al. 2014

View full text Add to dashboard Cite

Background: Few studies have reported the characterization of postnatal serum concentrations of endogenous free fatty acids (FFAs) in high-risk newborns and their effects on unbound bilirubin (UB). Methods: Serum concentrations of FFA, albumin (Alb), UB and total bilirubin (TB) were measured in 713 samples obtained within 5 days after birth from 439 newborns without intravenous lipid supplementation admitted to the neonatal intensive care unit (NICU). Serum FFA was reported as the day-specific percentile-based curve. Serum FFA and FFA/Alb ratios were compared in term and preterm patients. To assess the impact of FFA on UB, daily changes in FFA/Alb and UB/TB ratios were compared in term patients without receiving phototherapy or any drugs, and linear regression analysis was performed between FFA/Alb ratio and serum UB concentration or UB/TB ratio using 140 sera with hyperbilirubinemia of term and preterm patients. Results: A percentile-based curve showed that serum FFA peaked at 1 day of age and progressively decreased. Serum FFA and the FFA/Alb ratio were significantly higher in term than in preterm patients at birth and 1 and 3 days of age. FFA/ Alb ratio significantly changed over 5 days after birth, but UB/TB ratio remained constant. FFA/Alb ratio did not correlate with serum UB concentration or UB/TB ratio in sera with hyperbilirubinemia. Conclusions: We assessed postnatal concentrations of serum FFA in a large number of high-risk newborns admitted to the NICU. The concentration of endogenous FFAs in newborns admitted to the NICU was not rising until it influenced UB.

show abstract

Alterations in Reserve Bilirubin Binding Capacity of Albumin by Free Fatty Acids. II. In Vitro and In Vivo Studies Using Difference Spectroscopy

Cited by 11 publications

References 0 publications

Intravenous Lipid and Bilirubin-Albumin Binding Variables in Premature Infants

Intravenous Lipid and Bilirubin-Albumin Binding Variables in Premature Infants

Effect of Free Fatty Acids on Bilirubin–Albumin Binding Affinity and Unbound Bilirubin in Premature Infants

Postnatal serum concentrations of endogenous free fatty acids in newborns admitted to the neonatal intensive care unit: effects on unbound bilirubin

Contact Info

Product

Resources

About