SAT-028 Leptin, Leptin Soluble Receptor and FLI in Healthy and Preeclamptic Pregnancies
Authors: Paez-Leal Maria Carolina , Garces Maria Fernanda , Cano-Bermudez Maria Alejandra , Maldonado-Acosta Luis Miguel , Peralta-Franco Jhon Jairo , Franco-Vega Roberto , Ángel-Muller Edith , Parada-Banos Arturo José , Eslava-Schmalbach Javier Hernando , Rodríguez-Navarro Haiver Antonio , Buell-Acosta Julieth Daniela , Castano Justo Pastor , Nogueiras Ruben , Diéguez Carlos , Ruíz-Parra Ariel Ivan , Caminos Jorge Eduardo 
Published: May 2020

Abstract
Context
Leptin is an adipokine involved in many pleiotropic and key physiological actions and circulates free and active, or inactive bound to the leptin binding protein and sOB-r. Thus, the ratio Leptin/sOB-r or free leptin index (FLI) is commonly used as a marker of leptin sensitivity in different pathologies.
Objective
Evaluate serum concentrations of leptin and sOB-r and determine FLI in healthy pregnant and mild pre – eclamptic women in the three trimesters of gestation.
Design
A nested case-control study within a prospective cohort study of pregnant women, enrolled in the Department of Obstetrics and Gynecology of the School of Medicine at Universidad Nacional.
Main Outcome Measure and Methods
From the initial cohort, 46 healthy pregnant women and 19 mild pre – eclamptic pregnant women were randomly selected. Anthropometric, biochemical and clinical parameters were determined during three stages of pregnancy [1st (11.3±2.3 weeks), 2nd (24.4±3.10 weeks) and 3rd (34.84±4.41 weeks) periods of gestation]. Data were presented as mean ± SD. A p value &lt;0.05 was considered to be statistically significant.
Results
Serum leptin levels and sOB-r levels rose significantly throughout pregnancy in both healthy women [Leptin (1st 23.28±9.87 ng/mL; 2nd 34.58±18.45 ng/mL; 3rd 38.27±19.64 ng/mL trimester) (p=0.0001); sOB-r (1st 32.12±7.29 ng/mL; 2nd 43.26±9.25 ng/mL; 3rd 45.16±10.70 ng/mL trimester) (p&lt;0.0000)] and preeclamptic women [Leptin (1st 29.91±9.91 ng/mL; 2nd 47.10±25.70 ng/mL; 3rd 63.00±3012 ng/mL trimester) (p&lt;0.0000); sOB-r (1st 32.09±6.97 ng/mL; 2nd 37.54±6.33 ng/mL; 3rd 36.96±7.66 ng/mL trimester) (p=0.0380)].
Serum leptin levels were significantly higher in preeclamptic pregnant women compared to healthy pregnant women at 2nd (p=0.029) and 3rd trimesters of pregnancy (p&lt;0.000). Additionally, serum sOB-r levels were also significantly lower in pre - eclamptic pregnant women during the 2nd (p=0.017) and 3rd trimester (p=0.0036) of pregnancy compared to healthy pregnant women. As a result, the FLI index did not vary significantly during any of the three periods of pregnancy studied in healthy pregnant women [(1st 7.99±4.85; 2nd 8.72±6.5; 3rd 9.15±5.84 trimester) (p &gt;0.05)], whereas, in contrast, this index markedly increased throughout pregnancy in pre - eclamptic women [(1st 8.69±4.96; 2nd 13.54±8.78; 3rd 18.06±10.35 trimester) (p=0.0044)]. Indeed, the FLI index was significantly higher at 2nd (p=0.0186) and 3rd (p&lt;0.000) trimesters of pregnancy in pre - eclamptic women compared to healthy pregnant.
Conclusions
The present results demonstrate for the first time in a longitudinal study that FLI increases significantly in pre - eclamptic pregnant women towards the end of pregnancy. Hence, high FLI index values should be further explored as a potentially valuable indicator for the clinical manifestations of this pathology.