Adiponectin and catecholamine concentrations during acute exercise in children with type 1 diabetes

Objective: Adiponectin, an adipokine secreted by the adipocyte, is inversely related to adiposity and directly related to insulin sensitivity. In type 1 diabetes mellitus (T1DM), however, data thus far are contradictory. We investigated the relationship between adiponectin and exercise inT1DM. Methods: Forty-nine children (14.5 +/- 2.0 yr, range 8-17 yr) with T1DM on an insulin pump were studied during two 75-min exercise sessions with and without continuation of the basal rate within 4 wk. Adiponectin and epinephrine concentrations were measured before and during exercise. Results: Mean preexercise adiponectin concentration was 11.2 +/- 4.7 mg/L (range 2.7-23.0 mg/L) with a mean absolute difference of 1.7 mg/L between the 2 d. Adiponectin concentrations did not change meaningfully during exercise (mean change: -0.1 +/- 1.2 mg/L; p = 0.17). Adiponectin correlated inversely with body mass index percentile (p = 0.02) but not with age, gender, duration of diabetes, hemoglobin A1c, or preexercise glucose. However, those with higher baseline adiponectin concentrations were less likely to become hypoglycemic during exercise, 36% becoming hypoglycemic when baseline adiponectin concentration was < 10 mg/L, 42% when 10 to < 15 mg/L, and 15% when >= 15 mg/L (p = 0.02). Baseline epinephrine concentrations were not associated with adiponectin, and in those whose nadir glucose was <= 100 mg/dL, there was no correlation between epinephrine response and adiponectin (p = 0.16). Conclusions: Adiponectin concentrations are stable from day to day, are not affected by acute exercise or metabolic control, and vary inversely with adiposity. Higher adiponectin concentration appears to be associated with a decrease in hypoglycemia risk during exercise. Further studies are needed to examine whether adiponectin protects against exercise-induced hypoglycemia by directly enhancing the oxidation of alternate fuels.