Over expression of HSP70 and HSF1 in endothelial cells during pre-eclamptic placental stress

BACKGROUND AIM: Pre-eclampsia is a hypertensive disorder characterised by endothelial dysfunction and is one of the leading cause of preterm birth. Increasing oxidative stress and antioxidant disequilibria promote apoptosis and may play a defining role in the development of pre-eclampsia. Heat shock protein 70 (HSP70) is an effective molecular chaperone, playing a role in cell protection from damage in response to stress stimuli. This study focus on the expression of HSP70 in endothelial cells during pre-eclampsia compared with normotensive pregnant women.

The conjugated diene (CD), lipid hydro peroxide (LHP), total antioxidant capacity (TAC) analysis and glutathione redox ratio (GRR) are the stress specific parameters assessed in the placental endothelial cells of normotensive and pre-eclamptic subjects to evaluate the oxidative stress status. As the synthesis of HSP70 is regulated by a transcription factor, heat shock factor 1 (HSF1), its expression was also analysed.

There was a significant decrease in the viability (P < 0.05) of the endothelial cells isolated from pre-eclamptic subjects compared to normotensive subjects. The level of CD (P < 0.01) and LHP (P < 0.01) was increased with a simultaneous decrease in GRR (P < 0.05) and TAC (P < 0.05) levels in the endothelial cells of pre-eclamptic subjects compared to normotensive subjects. The expression of HSP70 (P < 0.05) and HSF1 (P < 0.05) was increased in pre-eclamptic subjects compared to normotensive subjects.

The over expression of HSP70 and HSF1 seen in the pre-eclamptic endothelial cells suggests its possible protective role as stress specific natural adaptive response against the generated stress.