Hyperglucagonemia in youth is associated with high plasma free fatty acids, visceral adiposity and impaired glucose tolerance

• Objective: To delineate mechanisms for fasting hyperglucagonemia in childhood obesity bystudying the associations between fasting plasma glucagon concentrations and plasmalipid parameters and fat compartments.Methods: Cross-sectional study of children and adolescents with obesity (n=147) and leancontrols (n=43). Differences in free fatty acids (FFA), triglycerides, insulin and fatcompartments (quantified by magnetic resonance imaging) across quartiles of fastingplasma glucagon concentration were analysed. Differences in OGTT glucagonresponse was tested in high vs low FFAs, triglycerides and insulin. Human islets ofLangerhans were cultured at 5.5 mmol/l glucose and in the absence or presence of aFFA mixture with total FFA concentration of 0.5 mmol/l and glucagon secretionquantified.Results: In children with obesity, the quartile with the highest fasting glucagon had higherinsulin (201±174 vs 83±39 pmol/l, p<0.01), FFAs (383±52 vs 338±109 μmol/l,p=0.02), triglycerides (1.5±0.9 vs 1.0±0.7 mmol/l, p<0.01), visceral adipose tissuevolume (1.9±0.8 vs 1.2±0.3 dm3, p<0.001) and a higher prevalence of impairedglucose tolerance (41% vs 8%, p=0.01) than the lowest quartile. During OGTT,children with obesity and high insulin had a worse suppression of glucagon during thefirst 10 minutes after glucose intake. Glucagon secretion was 2.6-fold higher in isletstreated with FFAs than in those not treated with FFAs.4Conclusion: Hyperglucagonemia in childhood obesity is associated with hyperinsulinemia, highplasma FFAs, high plasma triglycerides, visceral adiposity and impaired glucosetolerance. The glucagonotropic effect of FFAs on isolated human islets provides apotential mechanism linking high fasting plasma FFAs and glucagon levels.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Pediatrik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Pediatrics (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Endokrinologi och diabetes (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Endocrinology and Diabetes (hsv//eng)

Keyword

Childhood obesity

glucagon

free fatty acids

insulin

visceral adiposity

impaired glucose tolerance

type 2 diabetes

Publication and Content Type

ref (subject category)

art (subject category)