Impaired glucose tolerance is associated with increased serum concentrations of interleukin 6 and co-regulated acute-phase proteins but not TNF-alpha or its receptors.
OBJECTIVE
A population-based sample was studied to define immune abnormalities in individuals at risk of Type II (non-insulin-dependent) diabetes mellitus because of impaired glucose tolerance.


METHODS
A total of 1653 individuals aged 55 to 74 years participated in a population based survey in Southern Germany (KORA Survey 2000). Those without a history of diabetes were subjected to an OGTT. Randomly selected subjects with IGT ( n=80) were compared with non-diabetic control subjects ( n=77) and patients with Type II diabetes ( n=152) of the same population-based sample after matching for age and sex. Immune parameters were analysed in serum with rigidly evaluated ELISA.


RESULTS
Serum pro-inflammatory cytokine interleukin 6 (IL-6) concentrations were higher in subjects with IGT and Type II diabetes than in the control subjects (median 1.8 and 2.5 vs 0.8 pg/ml, p<0.0001). Soluble IL-6 receptors potentiate IL-6 bioactivity and their concentrations were mildly increased in Type II diabetes ( p<0.05). These immune changes seem relevant because IL-6 dependent acute-phase proteins C-reactive protein, serum amyloid A protein and fibrinogen were also increased in IGT and Type II diabetes. Circulating concentrations of TNF-alpha and its two receptors sTNF-R60 and sTNF-R80 were not increased in IGT subjects compared with the control subjects.


CONCLUSIONS
Our study shows systemic up-regulation of selected inflammatory mediators in patients with Type II diabetes and IGT. The pattern observed is non-random and fits with an IL-6 associated rather than TNF-alpha associated response.
Müller
S
S
German Diabetes Clinic, German Diabetes Research Institute at the University of Düsseldorf, Düsseldorf, Germany.
Martin
S
S
Koenig
W
W
Hanifi-Moghaddam
P
P
Rathmann
W
W
Haastert
B
B
Giani
G
G
Illig
T
T
Thorand
B
B
Kolb
H
H
D000209:Acute-Phase Proteins / Q000378:metabolism*; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000276:immunology* / Q000503:physiopathology; D005260:Female; D018149:Glucose Intolerance / Q000097:blood* / Q000276:immunology* / Q000503:physiopathology; D005951:Glucose Tolerance Test; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008055:Lipids / Q000097:blood; D008297:Male; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood*; D012016:Reference Values; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
D000209:Acute-Phase Proteins; D001786:Blood Glucose; D015850:Interleukin-6; D008055:Lipids; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha