Clinical study on the association between pregnancy-induced hypertension and insulin resistance

Abstract

The aim of the present study was to explore the association between pregnancy-induced hypertension (PIH) and insulin resistance (IR). A total of 50 cases of PIH and 50 healthy pregnant women with a similar gestational age were enrolled. The hyperinsulinemic-euglycemic clamp technique was used to evaluate the degree of IR and all 100 subjects were divided into an IR and a non-IR group accordingly. Subsequently, the correlation between the systolic or diastolic blood pressure was assessed; furthermore, a homeostasis model assessment of IR (HOMA-IR), a HOMA of the insulin sensitivity index (HOMA-ISI) and a HOMA of β cell function (HOMA-β%) were performed. Moreover, the effect of IR on PIH was assessed and the protein expression of insulin receptor substrate (IRS)-1, phosphorylated (p)-IRS-1, AKT and p-AKT were detected in the placental plasma by western blot analysis. The results showed that in the PIH group, the p-IRS-1/IRS-1 and p-AKT/AKT ratios were decreased compared with those in the control group. Blood flow parameters, including perfusion index, retinal resistive index and systolic maximum velocity/end-diastolic velocity ratio in the IR group were higher, while time averaged velocity was lower compared with that in the non-IR group. Furthermore, the HOMA-ISI and HOMA-β% were decreased, while the HOMA-IR was increased in the PIH group compared to that in the control group; alongside the blockage of the insulin signaling pathway, these factors may therefore cause PIH. The present study may provide novel therapeutic approaches for PIH.

Keywords: HOMA-IR; HOMA-ISI; HOMA-β%; insulin resistance; pregnancy-induced hypertension.

Figure 1.

Expression of (A and B) IRS-1 and p-IRS-1, and (C and D) AKT and p-AKT in the PIH and healthy control groups. Values are expressed as the mean ± standard deviation (n=50). *P<0.05 vs. Nor. p-IRS, phosphorylated insulin resistance substrate; PIH, pregnancy-induced hypertension; Nor, healthy control group.