Circulating Myonectin and Oxytocin Levels in Pediatric Obesity: A Comparative Study

TL;DR

The study found that obese children have lower levels of myonectin and higher levels of oxytocin compared to healthy children, suggesting changes in muscle and brain signaling related to obesity.

Contribution

The study identifies novel associations between myonectin and oxytocin levels and pediatric obesity, independent of BMI and insulin resistance.

Findings

Obese children had significantly lower circulating myonectin levels than healthy controls.

Obese children had significantly higher circulating oxytocin levels, independent of BMI and insulin resistance.

Abstract

What are the main findings?
•Children with obesity exhibited significantly lower circulating myonectin levels compared to healthy controls.•Circulating oxytocin levels were significantly higher in obese children and were independent of BMI-SDS and HOMA-IR.

Children with obesity exhibited significantly lower circulating myonectin levels compared to healthy controls.

Circulating oxytocin levels were significantly higher in obese children and were independent of BMI-SDS and HOMA-IR.

What are the implications of the main findings?
•Pediatric obesity may involve early alterations in muscle-derived metabolic signaling and neuroendocrine regulation beyond adipose tissue expansion.•Myonectin and oxytocin may serve as complementary biomarkers reflecting metabolic adaptation in childhood obesity.

Pediatric obesity may involve early alterations in muscle-derived metabolic signaling and neuroendocrine regulation beyond adipose tissue expansion.

Myonectin and oxytocin may serve as complementary biomarkers reflecting metabolic adaptation in childhood obesity.

Background/Objectives: The development of obesity is not only related to excessive adipose tissue accumulation but also involves complex inter-organ signaling pathways linking skeletal muscle and neuroendocrine systems. The present study aimed to evaluate circulating levels of myonectin (CTRP15), a skeletal muscle–derived metabolic regulator, and oxytocin, a neuropeptide with anorexigenic properties, in children with obesity. In addition, we examined the potential associations of these biomarkers with insulin resistance and metabolic risk indicators. Methods: This cross-sectional study included 53 children with obesity (body mass index standard deviation score [BMI-SDS] > 2) and 37 healthy children with normal body weight serving as controls. Anthropometric parameters, fasting glucose, insulin, lipid profile, and the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) index were assessed in all participants. Circulating concentrations of myonectin and oxytocin were measured and compared between groups, and correlations with metabolic variables were explored. Results: Children with obesity exhibited a less favorable metabolic profile characterized by higher HOMA-IR values, hyperinsulinemia, and elevated triglyceride levels. Serum myonectin concentrations were significantly lower in the obesity group compared with controls (4.01 ± 3.66 vs. 8.35 ± 12.00 ng/mL; p = 0.019). In contrast, circulating oxytocin levels were significantly higher among children with obesity (median [IQR] 156.2 [83.9–754.9] vs. 141.7 [47.7–221.5] pg/mL; p = 0.044). Neither hormone demonstrated a significant linear relationship with age, BMI-SDS, or HOMA-IR. Conclusions: Our findings indicate that childhood obesity is associated with reduced circulating myonectin levels and increased oxytocin concentrations. These observations suggest potential alterations in both muscle-derived metabolic signaling and neuroendocrine regulation in pediatric obesity. However, due to the cross-sectional design of the present study, causal relationships cannot be established.

Figures