624 - Impact of Enteral Docosahexaenoic Acid and Arachidonic Acid Supplementation on Fecal Biomarkers of Gut Inflammation and Defense in Preterm Infants

Publication Number: 2609.624

Omar Hayatt, Weill Cornell Medicine, New York, NY, United States; Divya Mandalaywala, Weill Cornell Medicine, New York, NY, United States; Martha Liu, Weill Cornell Medical College, New York, NY, United States; Liliette I. Quintana, Weill Cornell Medicine, New York, NY, United States; Cynthia Blanco, The University of Texas Health Science Center at San Antonio Joe R. and Teresa Lozano Long School of Medicine, San Antonio, TX, United States; Kara L. Calkins, University of CA Los Angeles, Los Angeles, CA, United States; Sarah Newell. Taylor, Yale School of Medicine, New Haven, CT, United States; Daniel T. Robinson, Northwestern University The Feinberg School of Medicine, Chicago, IL, United States; Steven Freedman, Beth Israel Deaconess Medical Center, Boston, MA, United States; Camilia R. Martin, Weill Cornell Medicine, New York, NY, United States

Background: Preterm infants acquire early postnatal deficits in circulating docosahexaenoic acid (DHA) and arachidonic acid (ARA), which are critical for organ development. The impact of enteral supplementation with DHA and ARA to mitigate postnatal deficits on markers of gut health is unknown.

Objective: To evaluate the impact of enteral DHA/ARA supplementation on fecal measures of inflammatory proteins and markers of intestinal injury and innate defenses in preterm infants.

Design/Methods: Preterm infants, 25 0/7 to 29 6/7 weeks' gestational age, enrolled in a clinical trial of enteral DHA/ARA supplementation, with plasma fatty acid levels and fecal samples available at 2 weeks of age (V14) and 36 weeks' postmenstrual age (W36), were included (n=48). Gas chromatography-mass spectrometry (GC-MS) quantified plasma fatty acids. Cumulative enteral DHA/ARA dose received was calculated and infants were stratified into one of three dose groups. Fecal lysates were assayed by multiplex/single-analyte ELISA for inflammatory proteins (IL1β, IL4, IL6, IL8, IL10, IL17A, IL22, TNFα), markers of intestinal injury (calprotectin, iFABP) and innate defense markers (iALP, zonulin). Generalized linear models were used to assess the association between fatty acid exposure and fecal biomarkers, while controlling for gestational age.

Results: At V14, plasma linoleic acid (LA) levels were inversely associated with IL1β (p < 0.05), and both ARA and DHA were inversely associated with IL6(p < 0.05,0.01) and iFABP (p < 0.01,0.05) (Fig1 Panel A). LA:DHA and ARA:DHA ratios were inversely related to fecal zonulin levels (p < 0.05,0.01). In contrast, DHA was positively associated with zonulin levels(p < 0.05). At W36, plasma ARA levels remained inversely associated with IL6 levels(p < 0.05), and ARA:DHA levels were inversely related to iFABP levels(p < 0.01) (Fig 1 Panel B). Fecal iFABP, IL17A, IL1 β IL6 levels decreased with increasing total dose exposure to the enteral supplement at two weeks of age (p < 0.05,0.05, 0.05, 0.01) (Fig 2). No association between total dose received and fecal biomarkers was noted at 36 weeks postmenstrual age (Fig 3).

Conclusion(s): Biochemical measures of gut health are influenced by systemic fatty acid levels and the total dose of enteral DHA/ARA supplement. Fecal measures of inflammatory proteins are negatively regulated by omega-6 fatty acid levels (LA and ARA), the omega-3 fatty acid DHA, and by LA:DHA and ARA:DHA ratios. These data reinforce the known anti-inflammatory effects of DHA and the critical role of ARA in early human development by regulating inflammation and innate intestinal defense proteins, such as zonulin.

Heatmap of Plasma Fatty Acid Levels Versus Fecal Biomarkers at V14 and W36 (Adjusted for Gestational Age)
Figure 1. Heatmap showing correlations between plasma fatty acids and ratios with fecal inflammatory proteins (IL-1β, IL-4, IL-6, IL-8, IL-10, IL-17A, IL-22, TNF-α), markers of intestinal injury (calprotectin and iFABP,) and innate defense markers (iALP, zonulin) at day 14 (V14) and 36 weeks PMA (W36), adjusted for gestational age. * = p<0.05, **=p < 0.01

Fecal Biomarkers By The Total Dose of Enteral DHA/ARA Supplementation Received at V14
Figure 2. Box-and-whisker plots showing fecal biomarker expression at V14 stratified by enteral DHA/ARA dose: Control: [0]mg/kg, Group 1 [360.3-747.5]mg/kg, Group 2 [747.5-863.6]mg/kg

Fecal Biomarkers By The Total Dose of Enteral DHA/ARA Supplementation Received at W36
Figure 3. Box-and-whisker plots showing fecal biomarker expression at W36 stratified by enteral DHA/ARA dose: Control: [0]mg/kg, Group 1 [1424.2-1895.4]mg/kg, Group 2 [1895.4-3969.3]mg/kg