January - March 2009, Volume 5, Issue 1

Mihu D, Georgescu C, Mihu C, Costin N, Blaga L, Pop R

High maternal serum leptin and interleukin-6 levels in pre-eclampsia and relationships with clinical and metabolical parameters of disease severity and pregnancy outcome

Acta Endo (Buc) 2009, 5 (1): 49-60
doi: 10.4183/aeb.2009.49

Background. The pathogenesis of pre-eclampsia involves inflammation, endothelial\r\ndysfunction and enhanced oxidative stress. Interleukin (IL)-6 is a major pro-inflammatory\r\ncytokine, while leptin is released in large amounts by the adipose tissue, but also by placenta.\r\nAim. The present study aims to evaluate total maternal serum leptin and IL-6 levels in\r\npre-eclampsia compared to normal pregnancy and non-pregnant status.\r\nMethods. We enrolled 65 women in a transversal study; pre-eclampsia was diagnosed\r\nin 25 (group 1), 25 women had a normal pregnancy (group 2), while in 15 pregnancy was\r\nexcluded. Groups were matched for chronological and gestational age and body mass index\r\n(BMI) accordingly. Total serum leptin and serum IL-6 were determined using ELISA, after\r\nan overnight fasting period of at least 12 hours.\r\nResults. Both leptin and IL-6 concentrations were significantly higher in women in the\r\nthird trimester of pregnancy developing pre-eclampsia compared to normotensive pregnant\r\nwomen (p=0.001). Normal pregnancy was characterized by increased serum leptin levels\r\n(p=0.001) as well as increased IL-6 levels (p=0.001) in comparison to non-pregnant status.\r\nIn women with pre-eclampsia, leptin was positively and significantly correlated with\r\ndiastolic blood pressure (r=0.45, p=0.02), proteinuria (r=0.48, p=0.01) and uric acid values\r\n(r=0.39, p=0.04) and inversely related to HDL cholesterol levels (r=-0.64, p=0.0001).\r\nLikewise, IL-6 was positively related to systolic and diastolic blood pressure (r=0.41,\r\np=0.008 and r=0.60, p=0.00003, respectively), proteinuria (r=0.38, p=0.01) and uric acid\r\nvalues (r=0.43, p=0.004). However, leptin had no correlation with pregnancy outcome in\r\nwomen with or without pre-eclampsia. In contrast, IL-6 was negatively correlated with both\r\nfetal birth at weight (r=-0.35, p=0.02) and Apgar score (r=-0.38, p=0.01).\r\nConclusions. In conclusion pre-eclampsia associates significantly increased serum\r\nleptin concentrations and IL-6 production compared to normal pregnancy. In contrast to\r\nleptin, IL-6 may predict pregnancy outcome (fetal birth weight and Apgar score) in women\r\nwith pre-eclampsia.

Keywords: leptin, interleukin-6, blood pressure, pregnancy, pre-eclampsia.

Correspondence: D. Mihu, MD, Department of Obstetrics Gynecology II, 55- 57, 21 Decembrie Blvd., 400124 Cluj-Napoca, Romania, Tel: 0722837213, Fax: 0264 596446, E-mail: dan.mihu@yahoo.com