Objective: To investigate the expression of lectin-liked oxidized low density lipoprotein receptor-1 (LOX-1) and apoptosis associated genes: caspase-3, Bax, and Bcl-2, in placenta and the relationship thereof with the morbility of early-onset preeclampsia.

Methods: 30 placentas of normal pregnant women at the 21+1 to 32 weeks gestation, 30 patients with early-onset preeclampsia at the 21+1 to 32 weeks gestation, 30 normal pregnant women at the 32+ weeks gestation to full term, and 30 patients with late-onset preeclampsia at the 32+ weeks gestation to full term. Immunohistochemistry, RT-PCR, and Western-blotting were used to detect the expression of LOX-1, caspase-3, Bax, and Bcl-2 in the placenta.

Results: The LOX-1 protein expression levels (grey levels) in the placenta tissues at 20W(+1) - 24W, 24W(+1) - 28W, and 28W(+1) - 32W gestation of the early-onset preeclampsia were 27.6 +/- 1.3, 29.4 +/- 1.4, and 32.3 +/- 1.6 respectively, all significantly higher than those of the normal pregnant women (11.2 +/- 0.6, 18.7 +/- 1.0, and 25.5 +/- 1.6 respectively, all P < 0.05). The LOX-1 protein levels at the 32W(+1) - 36W and 36W(+1) - 40W gestation of the late-onset preeclampsia patients were: 29.3 +/- 1.5 and 32.3 +/- 1.3 respectively, not significantly different from those of the normal pregnant women (28.1 +/- 1.8 and 31.3 +/- 1.6 respectively, both P > 0.05). The caspase-3 protein level Caspase-3 protein at 20W(+1) - 24W, 24W(+1) - 28W, and 28W(+1) - 32W gestation of the early-onset preeclampsia patients were 17.4 +/- 0.9, 23.2 +/- 1.1, and 28.4 +/- 0.8 respectively, all significantly higher than those of the normal pregnant women (8.5 +/- 1.0, 11.3 +/- 1.1, and 14.4 +/- 1.2 respectively, all P < 0.05). The caspase-3 protein levels at 32W(+1) - 36W and 36W(+1) - 40W gestation of the late-onset preeclampsia patients were 29.3 +/- 0.5 and 33.3 +/- 1.1 respectively, all significantly higher than those of the normal pregnant women (22.4 +/- 1.5 and 27.2 +/- 1.3 respectively, both P < 0.05). The Bax mRNA expression and protein expression of the early-onset preeclampsia patients were higher than those of the normal pregnant women, and the Bcl-2 mRNA expression and protein expression of the early-onset preeclampsia patients were lower than those of the normal pregnant women. The Bax mRNA expression and protein expression of the late-onset preeclampsia patients were still higher than those of the normal pregnant women; however, the Bcl-2 mRNA expression and protein expression of the late-onset preeclampsia patients were not significantly different from those of the normal pregnant women.

Conclusion: LOX-1 may be concerned with the pathogenesis of early onset of preeclampsia.