Fibroblast growth factor 21, adiposity, and macronutrient balance in a healthy, pregnant population with overweight and obesity

ABSTRACT

Aim of the study: The regulation and actions of fibroblast growth factor 21 (FGF21) are responsive to energy status and macronutrient balance, and investigations of FGF21 in normal pregnancy, which could be informative for FGF21 biology, are seldom. The goal of our study was to examine FGF21 levels in a contemporary healthy, pregnant population.

Methods: We phenotyped 43 women with overweight and obesity during pregnancy for weight, body composition, and fasting blood. Serum FGF21 was measured during the first and third trimesters. Placentas were collected at delivery.

Results: Maternal FGF21 concentrations were positively correlated with body mass index and adiposity, but not lean mass or glucose homeostasis. FGF21 concentrations significantly increased from the first to third trimester of pregnancy (0.105 vs. 0.256 ng/mL, p < 0.0001). Changes in FGF21 concentrations across pregnancy were not associated with changes in body weight or composition but inversely with the change in fasting glucose. FGF21 mRNA levels in placenta were very low and do not likely contribute to FGF21 in the maternal circulation.

Conclusions: FGF21 increases throughout pregnancy in our healthy cohort with overweight and obesity, independent of the placenta, and does not appear to be sensing the changes in energy balance (reflected in the change in maternal energy stores), but changes in macronutrient status. Thus, we propose FGF21 may be a potential signal of maternal nutrient status in pregnancy.

KEYWORDS:

• FGF21
• obesity
• placenta
• pregnancy

Acknowledgments

We graciously thank all the study subjects who participated in our studies as well as the clinical research staff, Mrs. Abby Altazan, Ms. Porsha Vallo, Mrs. Loren Cain, and Ms. Caitlin Hebert, who worked diligently in the collection of these data. We also thank Dr. Nicholas Broskey, Dr. Jenny Sones, Ms. Anik Boudreaux, and Mr. Hardy Hang for their guidance and technical support. We thank the LIFE-Moms consortium members for their contributions to the development and oversight of the common measures and procedures shared across the trials.

Declaration of interest

The authors have nothing to disclose.

Author contributions

EFS, CDM, JMS, and LMR conceived this study. EFS collected and analyzed the data. EFS and LMR wrote the manuscript. All authors approved the final version.

Supplementary Material

Supplemental data for this article can be accessed here.

Additional information

Funding

EFS was supported by Eunice Kennedy Shriver National Institute of Child Health and Human Development [F31HD084199]. The MomEE trial was supported by the NIDDK [R01DK099175]. LIFE-Moms was supported by the NIH through the NIDDK [U01DK094418 (Redman—Expecting Success), U01DK094463, U01DK094416, 5U01DK094466 (RCU)], NHLBI [U01HL114344, U01HL114377], NICHD [U01HD072834], NCCIH, the NIH Office of Research in Women’s Health (ORWH), the Office of Behavioral and Social Science Research (OBSSR), the Indian Health Service, and the Intramural Research Program of the NIDDK.