Subcutaneous and visceral adipose tissue lipidome in children reveals novel lipid species involved in obesity

Abstract

Overweight impacts over 390 million children and adolescents worldwide, of whom around 160 million are living with obesity. Adipose tissue biology in pediatric obesity is still relatively unknown. Adaptations to obesity including fat mobilization and remodeling are being investigated. The objective was to examine the lipidomic profile of subcutaneous and visceral adipose tissue (sWAT and vWAT, respectively) in children with obesity compared to those with normal weight, in order to identify novel lipid species modulated by obesity. Thirty pediatric patients with and without obesity were prospectively recruited at a referral single center and clinical data were reported. sWAT and vWAT samples were obtained for lipidomic analysis. Novel lipid species, including ether-linked triglycerides, ether-linked phosphatidylethanolamine, and oxidized triglycerides, were identified as altered in the sWAT from children with obesity compared with normal-weight children. These species are involved in beige adipose tissue development, energy metabolism, mitochondrial function, and oxidative stress. Compared with normal-weight children, the vWAT lipidome from children with obesity showed significant changes in some glycerophosphocholines, ceramides, and diglycerides, with accumulation of lipid species involved in inflammation, insulin resistance, and cardiovascular risk. The observed lipid correlations between vWAT and sWAT highlighted systemic dysregulation of lipid storage in childhood obesity, identifying both shared and depot-specific mechanisms of lipid handling. Our study reveals several critical lipid species that are modulated across both WAT depots, with notable implications for oxidative stress, lipid storage, and adipose tissue dysfunction. Key Points • The adipose lipidome of children with obesity showed specific alterations. • Lipid correlations revealed shared and depot-specific lipid handling mechanisms. • The altered lipid species had an impact on oxidative stress and insulin resistance.