Characterization of Wnt1-inducible Signaling Pathway Protein-1 in Obese Children and Adolescents

Wnt1-inducible signaling pathway protein-1(WISP1),a member of the CCN family,is increasingly being recognized as a potential target for obesity and type 2 diabetes mellitus.Recent studies have shown that WISP1 can regulate low-grade inflammation in obese mice,and circulating WISP1 levels are associated with obesity and type 2 diabetes mellitus in adults.Herein,we measured serum WISP1 levels in obese youth and explored its relationships with pro-inflammatory cytokine interleukin 18(IL-18)and other metabolic indexes.Totally,44 normal-weight and 44 obese children and adolescents were enrolled.Physical and laboratory data were recorded,and then serum levels of WISP1 and IL-18 were determined by enzyme-linked immunosorbent assays.Results showed that serum levels of WISP1 were significantly higher in obese children and adolescents than in normal-weight healthy controls (1735.444-15.29 vs. 1364.084-18.69 pg/mL).WISP1 levels were significantly positively correlated with body mass index (BMI)and BMI z-score (r=0.392,P=0.008;r=0.474,P=0.001,respectively) in obese group;circulating IL-18 was increased in obese individuals (1229.064-29.42 vs. 295.874-13.30 pg/mL).Circulating WISP1 levels were significantly correlated with IL-18 (r=0.542,P<0.001),adiponectin (r=0.585,P<0.001)and leptin (r=0.592,P<0.001).The multivariate stepwise regression analysis showed that higher IL-18 levels represented the main determinant of increased WISP1 levels after adjusting for BMI,waist circumference, fasting insulin,homeostatic model assessment of insulin resistance (HOMA-IR)and HbAlc in obese individuals (β=0.542,P=0.000).WISP1 can be involved in glucose/lipid metabolism in obese youth,which may be modulated by IL-18.Increased WISP1 levels may be a risk factor of obesity and insulin resistance,and WISP1 has a potential therapeutic effect on insulin resistance in obese children and adolescents.