Erythrocyte membrane lipidomics as a molecular tool for precision nutrition in children with obesity.

Abstract

Obesity is defined as a pathological condition characterized by an abnormal or excessive accumulation of fat, to the extent that it is considered a risk factor or marker for several chronic diseases.In this sense, molecular analysis tools such as metabolomics, genomics or the study of the intestinal microbiome allow us to advance in our knowledge of human metabolic behavior and favors the development of new diagnostic methods for obesity and its associated diseases.Lipids play a decisive role in obesity due to their structural and molecular signaling functions. Although the fatty acid (FA) composition of each tissue is specific, the mature red blood cell (RBC) is considered a good reporter of the metabolic state of different organs, tissues and cells, as it is a circulating cell and its membrane reflects an overall picture of the metabolism of each individual.For this reason, defining the mature RBC membrane FA profile will allow us to know the metabolic and nutritional status of the individuals studied, which is very useful in the molecular characterization of obesity.Taking these considerations into account, the aim of this thesis is to define the RBC membrane FAprofile that characterizes obese children, and to establish its relationship with metabolism and dietaryhabits, in order to be able to design precise nutritional strategies. To this end, a study was carried out in apopulation of normal-weight, overweight and obese children.In turn, a study was carried out to establish the respective differences in RBC membrane FA profilebetween adults and children with obesity, in order to be able to establish specific and personalizednutritional recommendations according to the differences observed by age, and derived from themetabolism of obesity itself.Statistical clustering techniques were also used to isolate a subgroup of obese children with a similar lipidprofile to normal-weight children. Analyzing the RBC membrane FA profile as a biomarker ofinflammation allows us to generate knowledge that contributes to the molecular characterization of theso-called metabolically healthy obese. At the same time, the absence of an inflammatory profile in thisgroup requires different nutritional recommendations tailored to their metabolic needs for effectiveinterventions.To re-establish the optimal composition of the RBC membrane FA profile, an adequate nutritionalstrategy must be established, comprised not only of an optimal diet adapted to specific metabolic needs,but in many cases, it must also be accompanied by the use of ¿-3 supplements, as these FAs have antiinflammatoryproperties and counteract the effects of excess ¿-6 FAs observed in obese children.From a precision nutrition point of view, knowing the RBC membrane FA profile of obese children,together with the integration of other molecular parameters, dietary habits, preferences and eatingbehavior, is of great interest to understand their relationship with the obesity metabolism, and to proposefuture nutritional intervention strategies, which may be effective in the long term, and reverse theincrease in prevalence of obesity