https://doi.org/10.37527/2021.71.S1
1Universidad de Guadalajara, Zapotlán el Grande, México.
Background and objective. Ghrelin and leptin are key hormones regulating appetite and metabolism, both circulate in bloodstream bound to serum proteins including low-affinity autoantibodies (autoAbs) directed against these hormones, specifically immunoglobulins of the G isotype (IgG). Eating behavior can be regulated by ghrelin and leptin and their alteration is associated with changes in body composition. The goal of this study was to analyze anti-ghrelin and anti-leptin autoAbs in sera from young adults and evaluate their correlation with body composition and appetitive traits.
Methods. Anti-ghrelin and anti-leptin IgG were measured in serum with a validated in-house ELISA test, which allows quantification of free, total fractions, and immune-complexes percentage. Body composition was measured by bioelectrical impedance. Appetitive traits were assessed via the Adult Eating Behaviour Questionnaire, which comprises 4 ‘food approach’ subscales. Food Responsiveness (FR), Enjoyment of Food (EF) and Emotional overeating (EOE) and 4 ‘food avoidance’ subscales. Satiety Responsiveness (SR), Emotional under-eating (EUE), Food Fussiness (FF) and Slowness in Eating (SE).
Results. One hundred and eighty adults were included in the study (mean age 20±2 years), 69% were females. 46% of the subjects had an ideal body fat percentage (BF%) and 54% had above-average BF%. Correlation analysis were made according to sex and BF%. Both anti-ghrelin and anti-leptin immune-complexes showed a positive correlation between waist-hip ratio (r=0.21,p=0.0044 and r=0.17,p=0.0180, respectively). In women, free and total anti-ghrelin autoAbs were higher in those who scored lower in EF and FF appetitive traits (p=0.0293,p=0.0328, respectively); immune-complexes were higher in those who scored higher in EF (p=0.0258). In men, free anti-leptin autoAbs were higher in subjects who scored higher in EUE (p=0.0294) whereas immune-complexes were higher in those who scored lower in EUE (p=0.0282).
Conclusion. These results support the role of IgG autoantibodies directed against ghrelin and leptin as carriers/protective of the hormone and evidence of their potential contribution in regulating eating behavior.