Citation: Soria-Gondek, A.; Fernández-García, P.; González, L.; Reyes-Farias, M.; Murillo, M.; Valls, A.; Real, N.; Pellitero, S.; Tarascó, J.; Jenkins, B.; et al. Lipidome Profiling in Childhood Obesity Compared to Adults: A Pilot Study. Nutrients 2023, 15, 3341. https://doi.org/10.3390/ nu15153341 Academic Editor: Ashley J. Snider Received: 22 June 2023 Revised: 13 July 2023 Accepted: 25 July 2023 Published: 27 July 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). nutrients Article Lipidome Profiling in Childhood Obesity Compared to Adults: A Pilot Study Andrea Soria-Gondek 1,† , Pablo Fernández-García 2,† , Lorena González 3 , Marjorie Reyes-Farias 3,4 , Marta Murillo 5 , Aina Valls 5 , Nativitat Real 6 , Silvia Pellitero 7 , Jordi Tarascó 8 , Benjamin Jenkins 9 , María Galán 2 , Francesc Villarroya 10,11 , Albert Koulman 9 , Patricia Corrales 2 , Antonio Vidal-Puig 12 , Rubén Cereijo 10,11,13, * and David Sánchez-Infantes 2,3,11, * 1 Pediatric Surgery Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain; andreasoriagondek@gmail.com 2 Department of Health Sciences, Campus Alcorcón, University Rey Juan Carlos (URJC), 28922 Madrid, Spain; pablo.fernandezga@urjc.es (P.F.-G.); mgalana@urjc.es (M.G.); patricia.corrales@urjc.es (P.C.) 3 Fundació Institut Germans Trias i Pujol, 08916 Barcelona, Spain; lorenagl.lorena@gmail.com (L.G.); marjorie.reyesfarias@ub.edu (M.R.-F.) 4 Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain 5 Pediatric Endocrinology Unit, Pediatric Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain; mmurillo.germanstrias@gencat.cat (M.M.); ainavalls@hotmail.com (A.V.) 6 Pediatric Nurse, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain; nereal.germanstrias@gencat.cat 7 Endocrinology Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain; spellitero.germanstrias@gencat.cat 8 General Surgery Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain; jtarasco@me.com 9 NIHR BRC Core Metabolomics and Lipidomics Laboratory, Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 1GG, UK; bjj25@medschl.cam.ac.uk (B.J.); ak675@medschl.cam.ac.uk (A.K.) 10 Biochemistry and Molecular Biomedicine Department, Institut de Biomedicina de la Universitat de Barcelona (IBUB), 08028 Barcelona, Spain; fvillarroya@ub.edu 11 Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBERobn), 28029 Madrid, Spain 12 Institute of Metabolic Science, Addenbrooke’s Hospital, University of Cambridge, Cambridge CB2 1GG, UK; ajv22@medschl.cam.ac.uk 13 Institut de Recerca Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain * Correspondence: rcereijo@ub.edu (R.C.); david.sanchezi@urjc.es (D.S.-I.); Tel.: +34-914888882 (D.S.-I.) † These authors contributed equally to this work. Abstract: The objective is to assess the circulating lipidome of children with obesity before and after lifestyle intervention and to compare the data to the circulating lipidome of adults with obesity before and after bariatric surgery. Ten pediatric (PE) and thirty adult (AD) patients with obesity were prospec- tively recruited at a referral single center. The PE cohort received lifestyle recommendations. The AD cohort underwent bariatric surgery. Clinical parameters and lipidome were analyzed in serum before and after six months of metabolic intervention. The abundance of phosphatidylinositols in the PE cohort and phosphatidylcholines in the AD significantly increased, while O-phosphatidylserines in the PE cohort and diacyl/triacylglycerols in the AD decreased. Fifteen lipid species were coincident in both groups after lifestyle intervention and bariatric surgery. Five species of phosphatidylinositols, sphingomyelins, and cholesteryl esters were upregulated. Eight species of diacylglycerols, glyc- erophosphoglycerols, glycerophosphoethanolamines, and phosphatidylcholines were downregulated. Most matching species were regulated in the same direction except for two phosphatidylinositols: PI(O-36:2) and PI(O-34:0). A specific set of lipid species regulated after bariatric surgery in adult individuals was also modulated in children undergoing lifestyle intervention, suggesting they may constitute a core circulating lipid profile signature indicative of early development of obesity and improvement after clinical interventions regardless of individual age. Nutrients 2023, 15, 3341. https://doi.org/10.3390/nu15153341 https://www.mdpi.com/journal/nutrients