Associations of Size at Birth and Metabolic Syndrome Antecedents With Serum Spexin Levels in Prepubertal Children

Background: Spexin is a novel peptide implicated in food intake and obesity. The primary aim of this study was to analyze whether serum spexin levels, along with total leptin and active ghrelin levels were different in prepubertal children born small for gestational age(SGA) and appropriate for gestational(AGA). Secondary aims were to analyze whether serum spexin, leptin and active ghrelin levels correlated with metabolic syndrome(MS)antecedents according to the Dietary and lifestyle-induced health effects in children and infants (IDEFICS)study. Subjects and Methods: We conducted a cross-sectional study on prepubertal37SGA- (median:5.6yr)and50prepubertalAGA-born children(median:5.9yr). Anthropometric data, homeostasis model assessment of insulin resistance(HOMAIR),plasma lipids, serum spexin, total leptin and active ghrelin levels were analyzed. Associations of serum spexin levels with MS antecedents according to the IDEFICS study were investigated. Results: Children bornSGA had higher body mass index and waist circumference than AGA-born peers(p <0.05). Serum total leptin levels were higher in SGA-born children than in AGA-born peers (p<0.05). Plasma active ghrelin and spexin levels were not different between the subgroups(p>0.05). Children bornSGA had higher MS risk scores than AGA-born peers(p <0.05). Small for gestational age- born children had higher plasma glucose,insulin and HOMA-IR than AGA-born peers(p<0.05). In children born SGA, the number of subjects with excess adiposity (N(SGA)=18(43.9%)andN(AGA)=7(14%),p=0.016)and insulin resistance(N(SGA)=14(34%) andN(AGA)=6(12%),p=0.035)was higher than in AGA-born peers. There was no significant difference in frequency of dyslipidemia between the subgroups(p=0.19). The frequency of children with more than one MS antecedent was higher in SGA-born children than in AGA-born peers(Chi-Square p <0.01). Metabolic syndrome risk score according to IDEFICS was higher in SGA born children than in AGA-born peers(2.2±1.8vs1.1±1.8;p=0.008). Serum spexin levels were lower in children with MS antecedents than those without MS antecedents in both AGA -and SGA-born children[Serum spexin levels in AGA-born children with and without MS antecedents: 48,5pg/mL(25-75%IQR:19.8-93.8pg/mL)and143pg/mL(25-75%IQR:104-211pg/mL),p<0.001;respectively, serum spexin levels inSGAborn children with and without MS antecedents: 31,0pg/mL(25-75%IQR:16.5-47.0 pg/mL) and79.5pg/mL(25-75% IQR:49.5-274.8pg/mL),p=0,0016;respectively]. In the whole study group, the most important factor associated with excess adiposity was history of being born SGA(OddsRatio=91.3[95%CI:2.2-374;p=0.017] Conclusions: Serum spexin levels were not different inSGA- and AGA-born children. Serum spexin levels were reduced in children with MS antecedents independent of size at birth.