Amylin and its relation to insulin and lipids in obese children before and after weight loss

Vestische Hospital for Children and Adolescents Datteln, University of Witten/Herdecke, Dr. F. Steiner Str. 5, 45711 Datteln, Germany.
Obesity (Impact Factor: 4.39). 09/2007; 15(8):2006-11. DOI: 10.1038/oby.2007.239
Source: PubMed

ABSTRACT There are limited data concerning the relationships between amylin, weight status, lipids, insulin, and insulin resistance in obese humans. Therefore, the aim was to study these relationships in cross-sectional and longitudinal analyses.
Fasting amylin, insulin, glucose, triglycerides, low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol, and percentage body fat based on skinfold measurements were determined in 37 obese children (median age, 11.5 years) and compared with 16 lean children of the same age and gender. Furthermore, we analyzed the changes of these variables in the obese children after participating in a one-year weight loss intervention program.
Obese children had significantly (p < 0.01) higher amylin, triglycerides, LDL-cholesterol, and insulin levels as compared with the lean children. In multiple linear regression analysis, amylin was significantly (p < 0.05) correlated to insulin and triglycerides, but not to age, gender, pubertal stage, or BMI. Changes of amylin correlated significantly (p < 0.001) to changes of insulin (r = 0.54) and triglycerides (r = 0.49), but not to changes of BMI or percentage body fat. Substantial weight loss in 17 children led to a significant (p < 0.05) decrease of amylin, triglycerides, and insulin, in contrast to the 20 children without substantial weight loss.
Amylin levels were related to insulin concentrations in both cross-sectional and longitudinal analyses, suggesting a relationship between amylin and insulin secretion. Amylin levels were reversibly increased in obesity and related to triglyceride concentrations.

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