Circulating pro- and anti-inflammatory cytokines in Polish women with gestational diabetes

In this study we measured serum concentrations of proinflammatory interleukin-6, interleukin-8, and interleukin-18 as well as anti-inflammatory interleukin-10 in 30 pregnant women with normal glucose tolerance, in 32 women with abnormal results of a 50-g glucose challenge test, and in 57 patients with gestational diabetes mellitus. Patients with gestational diabetes had significantly higher IL-6 (median 1.0 [0.7-1.5] vs. 0.7 [0.4-0.8] pg/ml, p = 0.001), IL-8 (2.1 [1.1-4.2] pg/ml vs. 0.7 [0.4-0.9] pg/ml, p < 0.0001), and IL-18 (249.3 [188.5-318.7] pg/ml vs. 186.7 [139.9-243.9] pg/ml, p = 0.005) as well as lower IL-10 levels than healthy pregnant women 0.6 [0.5-1.5] pg/ml vs. 2.9 [1.8-3.2] pg/ml, p < 0.0001). After adjusting for glucose, insulin, and BMI values, the differences in IL-8 and IL-18 became insignificant, whereas the differences in IL-6 and IL-10 levels remained highly significant (p < 0.0001). The subjects with abnormal glucose challenge test results had higher IL-6 levels (0.9 [0.7-1.3] pg/ml, p = 0.005) and similar levels of other cytokines as compared with the women with normal glucose tolerance. Our results suggest an impaired balance between circulating pro- and anti-inflammatory cytokines in patients with gestational diabetes; however, a significant contribution of maternal obesity to the increased levels of IL-8 and IL-18 should be underlined.