Amalgamation of Toll-Like Receptor and Hypoxic Signaling in Etiology of Preeclampsia

Inflammation and oxidative stress are involved in the pathogenesis of preeclampsia. Therefore, the aim of this study was to investigate the expression of Toll-like receptor (TLR) (TLR-4, HMGB1, NFκB, IκBα) and hypoxic (HIF-1α, HIF-1β, PHD, pVHL) pathway proteins in the placenta of preeclamptic pregnant women after 28 weeks of gestational period. A possible association between these 2 pathways was also explored. A total of 194 placental tissues of preeclamptic as well as healthy pregnant women were analyzed by immunohistochemistry. On the basis of gestational age, the samples were divided into 2 groups, I (28-36 wk) and II (36 wk onwards), with 55 and 139 samples in the respective groups. The expression of both TLR (TLR-4, HMGB1, NFκB, IκBα) and hypoxic (HIF-1α, HIF-1β, PHD, pVHL) pathway proteins were significantly modulated in the placental tissues of preeclampsia as compared with control. The 2 pathways were interlinked in preeclampsia. This study highlights the intercorrelation of both TLR and hypoxic signalling pathways that may be a causative factor for the pathophysiology of preeclampsia.