Mature subcutaneous and visceral adipocyte concentrations of adiponectin are highly correlated in prepubertal children and inversely related to body mass index standard deviation score.

CONTEXT

Adiponectin is an adipocyte-specific protein with insulin-sensitizing properties. Several studies have examined the expression of adiponectin mRNA or tissue/secreted protein levels in fat obtained from adults, but none has assessed tissue levels in childhood.

PATIENTS

Paired subcutaneous (Sc) and visceral (V) fat samples were obtained from 12 normal-weight children.

MAIN OUTCOME MEASURES

Mature adipocytes were isolated and total adiponectin levels determined by ELISA. Insulin sensitivity and lipid parameters were assessed in fasting blood samples taken at the time of biopsy collection.

RESULTS

A positive correlation was seen between the adiponectin concentration within the Sc and V mature adipocytes derived from each child (r = 0.924; P < 0.001). After logarithmic transformation of the Sc and V adiponectin concentrations (log-Sc and log-V) to render the data Gaussian, both log-Sc and log-V were found to be lower in those children with higher body mass index sd score (r = -0.621 and r = -0.357 respectively), although this reached statistical significance only in the Sc adipocytes (P = 0.03). Age was not related to either log-Sc or log-V adiponectin levels, although a significant negative association was seen with serum adiponectin (r = -0.589; P = 0.04). Log-Sc or log-V did not correlate with serum adiponectin concentrations, markers of insulin sensitivity, or circulating lipid levels.

CONCLUSIONS

These data indicate a relationship between total adiponectin levels in different tissue compartments, suggesting either some form of interaction or coregulation by systemic factors, possibly related to body size/fat mass. Serum concentrations of total adiponectin were inversely related to age but showed no relationship with either tissue levels or body mass index sd score.