Cheng HL, Sainsbury A, Garden F, Sritharan M, Paxton K, Luscombe G, Hawke C, Steinbeck K. Ghrelin and peptide YY change during puberty: relationships with adolescent growth, development, and obesity. The Journal of Clinical Endocrinology and Metabolism 2018;103:2851-60

Abstract

Context: Pubertal adolescents show strong appetites. How this is mediated is unclear, but ghrelin and peptide YY (PYY) play potentially important roles.

Objective: To measure ghrelin and PYY change in relation to pubertal growth.

Design: Three-year prospective cohort study.

Setting: Australian regional community.

Participants: Eighty healthy adolescents (26 girls; 54 boys) recruited at 10 to 13 years.

Main Outcome Measures: Fasting circulating total ghrelin, total PYY, IGF-1, insulin, leptin (via radioimmunoassay), estradiol and testosterone (via mass spectrometry), anthropometry, and body composition (via bioelectrical impedance).

Results: Adolescents exhibited normal developmental change. Mixed models revealed positive associations for ghrelin to age2 (both sexes: P < 0.05), indicating a U-shaped trend over time. Ghrelin was also inversely associated with IGF-1 (both sexes: P < 0.05), leptin in girls (P < 0.01), and insulin in boys (P < 0.05) and negatively correlated with annual height and weight velocity (both sexes: P ≤ 0.01). PYY showed no age-related change in either sex. Neither ghrelin nor PYY were associated with Tanner stage. Weight subgroup analyses showed significant ghrelin associations with age2 in healthy-weight but not overweight and obese adolescents (7 girls; 18 boys).

Conclusions: Adolescents showed a U-shaped change in ghrelin corresponding to physical and biochemical markers of growth, and no change in PYY. The overweight and obesity subgroup exhibited an apparent loss of the U-shaped ghrelin trend, but this finding may be attributed to greater maturity and its clinical significance is unclear. Further research on weight-related ghrelin and PYY trends at puberty is needed to understand how these peptides influence growth and long-term metabolic risk.