Interleukin-10 (IL-10) appears to be the key
cytokine for the maintenance of pregnancy and inhibits the secretion of inflammatory
cytokines such as
tumor necrosis factor-α (TNF-α). However, there are no studies evaluating the profile of these
cytokines in diabetic rat models. Thus, our aim was to analyze
IL-10 and TNF-α immunostaining in placental tissue and their respective concentrations in maternal plasma during
pregnancy in diabetic rats in order to determine whether these
cytokines can be used as predictors of alterations in the embryo-fetal organism and in placental development. These parameters were evaluated in non-diabetic (control; N = 15) and Wistar rats with
streptozotocin (STZ)-induced diabetes (N = 15). At term, the dams (100 days of life) were killed under
anesthesia and plasma and placental samples were collected for
IL-10 and TNF-α determinations by ELISA and immunohistochemistry, respectively. The reproductive performance was analyzed. Plasma
IL-10 concentrations were reduced in STZ rats compared to controls (7.6 ± 4.5 vs 20.9 ± 8.1 pg/mL). The placental scores of immunostaining intensity did not differ between groups (P > 0.05). Prevalence analysis showed that the
IL-10 expression followed TNF-α expression, showing a balance between them. STZ rats also presented impaired reproductive performance and reduced plasma
IL-10 levels related to damage during early embryonic development. However, the increased placental
IL-10 as a compensatory mechanism for the deficit of maternal regulation permitted embryo development. Therefore, the data suggest that
IL-10 can be used as a predictor of changes in the embryo-fetal organism and in placental development in pregnant diabetic rats.