273 - Differences in the umbilical cord blood metabolome in pregnancies of mothers affected by obesity and those with normal weight

Poster Number: 273
Publication Number: 273.119

Svetlana Kozlovich, Medical College of Wisconsin, Milwaukee, WI, United States; Amy Pan, Medical College of Wisconsin, Milwaukee, WI, United States; pippa m. simpson, MCW, milwaukee, WI, United States; T. Hang Nghiem-Rao, Medical College of Wisconsin, Milwaukee, WI, United States

Background: Infants born to mothers with obesity are at increased risk for metabolic syndrome, however intrauterine exposures that may predispose to later disease are not well understood.

Objective: To identify differences in the umbilical cord blood metabolome of term pregnancies of mothers with obesity and normal weight mothers.

Design/Methods: Cord blood samples from pregnancies of otherwise healthy mothers with obesity (BMI >30 kg/m2) and normal weight mothers (BMI < 25kg/m2), matched for maternal age group and mode of delivery, were obtained from the Medical College of Wisconsin Tissue Bank. Metabolomic profiling was performed with untargeted LC-MS, metabolites were characterized and identified using standard protocols. Pathway analysis was done using MetaboAnalyst.

Results:
Cord blood samples were obtained from 15 obese and 15 normal weight pregnancies. Overall, the mean maternal age was 28.7+/-3.3 years, gestational age 39.4+/-0.6 weeks, infant birth weight 3.7+/-0.3 kg. There were no differences in maternal age, ethnicity, gravidity, parity, pregnancy weight gain; or infant gestational age, birth weight, and sex between groups.

 

10092 metabolites were considered reliable based on quality of the data. 183 metabolites were differentially abundant ( >40% difference in abundance and p-value < 0.05) between obese and normal weight samples, 55% were unknown compounds, 42% were assigned a prospective formula, 3% were known compounds. Among the 82 metabolites that were known or assigned a prospective formula, 83% had higher abundance and 17% had lower abundance in obese compared to normal weight samples. Obese samples had higher levels of metabolites identified as fatty acyls (35%), organic acids (12%), and organoheterocyclic compounds (12%); and lower levels of organoheterocyclic compounds (21%), organic acids (14%), and sterol lipids (14%).

 

The most abundant metabolites in obese compared to normal weight samples were the sphingolipid PE-Cer(d37:4) ( >5 fold higher), O-desmethylnaproxen (2.8 fold), trihomomethionine (2.3 fold), and unsaturated fatty acids undecenoic acid (2.1 fold) and heptacosatrienoic acid (1.9 fold), (all p-values < 0.05).

 

From MetaboAnalyst, metabolomic differences were predicted to be associated with glutathione metabolism, primary bile acid biosynthesis, and porphyrin and chlorophyll metabolism (Impact 0.26, 0.06, and 0.05, respectively, all p-value < 0.05).
Conclusion(s): Lipid metabolites are higher in umbilical cord samples of obese compared to normal weight pregnancies. Excess intrauterine lipid exposure may increase inflammation in infants of obese pregnancies.