Pediatr Gastroenterol Hepatol Nutr.  2012 Sep;15(3):166-174.

Leptin, Neuropeptide Y and Islet Amyloid Polypeptide Levels in Obese Children

• Choi MS
• Jee SH
• Kim EY
• Moon KR

Abstract

PURPOSE
The aim of this study was to compare serum leptin, neuropeptide Y (NPY), and islet amyloid polypeptide (amylin) levels in obese and normal weight children, and to investigate their correlations with anthropometric parameters and metabolic bio-marker levels.
METHODS
Body mass index (BMI), waist and hip circumference, blood pressure (systolic/diastolic), lipid profile, fasting glucose, and serum insulin, leptin, NPY, and amylin levels were measured in 56 children (24 obese children and 32 non-obese controls). Homeostatic model assessment-insulin resistance (HOMA-IR) values were calculated and the relationships between anthropometric variables, metabolic biomarkers, and diet-regulating factors (leptin, NPY, and amylin levels) were examined.
RESULTS
BMI, hip circumference, waist circumference, and systolic and diastolic pressure were significantly higher in the obese group than in the non-obese group (p<0.0001). Total cholesterol, triglyceride, low-density lipoprotein-cholesterol, glucose, and insulin levels were also significantly higher in the obese group (p<0.05). On the other hand, high-density lipoprotein-cholesterol levels were higher in the non-obese group , but this was not significant. Serum leptin, NPY, and amylin levels were significantly higher in the obese group (p<0.05). Furthermore, in the obese group, leptin levels were found to be significantly correlated with BMI (r=0.379, p=0.043), and NPY levels (r=0.377, p=0.044), and amylin levels were found to be significantly correlated with insulin levels (r=0.400, p=0.048), and HOMA-IR (r=0.459, p=0.028).
CONCLUSION
Metabolic risk factor alterations are present in obese children, and these children show abnormalities in the diet regulatory system caused by leptin, NPY, and amylin resistance. Of particular note, amylin was found to be positively correlated with insulin resistance.

Keyword

Leptin; Neuropeptide Y; Islet amyloid polypeptide; Childhood obesity

MeSH Terms

Biomarkers
Blood Pressure
Body Mass Index
Child
Cholesterol
Diet
Fasting
Glucose
Hand
Hip
Humans
Insulin
Insulin Resistance
Islet Amyloid Polypeptide
Leptin
Neuropeptide Y
Neuropeptides
Risk Factors
Waist Circumference
Cholesterol
Glucose
Insulin
Islet Amyloid Polypeptide
Leptin
Neuropeptide Y
Neuropeptides

Figure

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  Fig. 1 Comparisons of diet-regulating factors in the normal control and obese groups. Values are presented as mean±standard deviation. (A) Leptin, (B) Neuropeptide Y, (C) Amylin.

• 

  Fig. 2 The correlation between leptin levels and BMIs (A) and NPY levels (B) in the obese group. BMI: body mass index, NPY: neuropeptide Y.

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  Fig. 3 Correlations between amylin and insulin levels (A), and between amylin levels and HOMA-IR values (B) in the obese group. HOMA-IR: homeostatic model assessment-insulin resistance.

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