Proinflammatory and atherogenic activity of monocytes in type 2 diabetes.
Cytokines secreted by the monocyte-macrophage system play a key role in the progression of atherosclerotic lesions in Type 2 diabetes. The objectives of this study were to assess the influence of cytokine gene expression in monocytes from patients with Type 2 diabetes on direct markers of endothelial injury with regard to clinically manifest atherosclerosis.


METHODS
Monocytes from 58 patients with Type 2 diabetes and from 22 age-matched healthy volunteers of a control group were isolated in order to assess expression of tumor necrosis factor alpha (TNFalpha), interleukin (IL)-6, IL-8 and IL-10 cytokines (RTPCR, Applied Biosystems). Thrombomodulin concentration was determined using a Diagnostica Stago Immunoenzymatic assay, and circulating endothelial cell numbers were assayed using immunofluorescence studies with CLB-HEC19 antibodies.


RESULTS
In 28 patients, TNFalpha expression in monocytes was observed. In these patients, as compared to those with undetectable levels of this cytokine's expression, higher hemoglobin A(1c) (P=.012) and thrombomodulin (P=.005) concentrations were found. IL-8 expression was determined in 36 patients. Higher expression of TNFalpha (P=.048) and IL-8 (P=.049) was detected in patients with peripheral arterial disease in contrast to those free from this complication.


CONCLUSIONS
TNFalpha and IL-8 play a significant role in the proatherogenic activity of monocytes in Type 2 diabetes. The TNFalpha-connected activity of monocytes may directly determine endothelial dysfunction and injury. The location of atherosclerosis should be taken into account in the assessment of the proinflammatory activity of peripheral blood monocytes.
Gacka
Małgorzata
M
Department of Angiology, Diabetology and Hypertension, Medical University of Wrocław, Wrocław, Poland. magacka@poczta.onet.pl
Dobosz
Tadeusz
T
Szymaniec
Stanisław
S
Bednarska-Chabowska
Dorota
D
Adamiec
Rajmund
R
Sadakierska-Chudy
Anna
A
D000328:Adult; D000368:Aged; D050197:Atherosclerosis / Q000209:etiology / Q000503:physiopathology*; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D016207:Cytokines / Q000097:blood / Q000235:genetics / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000097:blood / Q000150:complications; D042783:Endothelial Cells / Q000166:cytology; D005260:Female; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000503:physiopathology*; D007333:Insulin Resistance / Q000502:physiology; D016209:Interleukin-8 / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018180:Thrombomodulin / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000235:genetics / Q000378:metabolism*
D015415:Biomarkers; D016207:Cytokines; D016209:Interleukin-8; D018180:Thrombomodulin; D014409:Tumor Necrosis Factor-alpha