Serum Levels of Fetal Antigen 1 in Extreme Nutritional States

Alin Andries,Rene K Støving,Andreas Niemeier,Moustapha Kassem,Basem M Abdallah,Kirsten Hørder,Anna-Maria Wolf

doi:10.5402/2012/592648

Abstract

Objective. Recent data suggest that fetal antigen (FA1) is linked to disorders of body weight. Thus, we measured FA1 serum levels in two extreme nutritional states of morbid obesity (MO) and anorexia nervosa (AN) and monitored its response to weight changes. Design. FA1 and insulin serum concentrations were assessed in a cross-sectional study design at defined time points after gastric restrictive surgery for 25 MO patients and 15 women with AN. Results. Absolute FA1 serum levels were within the assay normal range and were not different between the groups at baseline. However, the ratio of FA1/BMI was significantly higher in AN. FA1 was inversely correlated with BMI before and after weight change in AN, but not in MO patients. In addition, MO patients displayed a significant concomitant decrease of FA1 and insulin with the first 25% of EWL, while in AN patients a significant increase of FA1 was observed in association with weight gain. Conclusion. FA1 is a sensitive indicator of metabolic adaptation during weight change. While FA1 serum levels in humans generally do not correlate with BMI, our results suggest that changes in FA1 serum levels reflect changes in adipose tissue turnover.

Highlights

Fetal antigen 1 (FA1), known as preadipocyte factor 1 or Delta-like 1 (Dlk1), was originally isolated from amniotic fluid [1]
In order to further elucidate the relationship between circulating FA1 levels and changes in body weight in humans, we studied two extreme nutritional states, morbid obesity (MO) and anorexia nervosa (AN), before and after weight change
We observed a significant increase in FA1 levels in AN patients upon weight gain

Summary

Introduction

Fetal antigen 1 (FA1), known as preadipocyte factor 1 (pref-1) or Delta-like 1 (Dlk1), was originally isolated from amniotic fluid [1]. It is a member of the epidermal growth factor (EGF) superfamily. FA1 is expressed in neuroendocrine tissues, for example insulin producing beta cells of the islets of Langerhans, growth hormone producing cells in the pituitary gland [4], adrenal glands, and sex hormone-producing cells of the gonads [3, 5], as well as specific areas in the central nervous system [6]. FA1 can be measured in serum and body fluids using ELISA assay, and its levels do not differ between males and females. Serum FA1 does not exhibit age-related changes beyond adolescence, diurnal variation, or variations during the menstrual cycle [11, 12]

Methods

Results

Discussion

Conclusion