Endocrine Abstracts

Background and aims: The mechanisms underlying placenta oxidative stress co-existing with alterations in maternal-placenta interactions during gestational diabetes mellitus (GDM) are not well understood. We sought to evaluate the levels of oxidative stress markers and antioxidants in women with GDM, and to assess the impact on placenta.

Material and methods: Pregnant women (63 with GDM, 63 controls) were enrolled, together with 41 cases and 21 controls for the follow-up study. Oxidative stress markers and antioxidants were measured between the 24–29th week of gestation and 12 months post-delivery as well as in placentae from 6 controls and 6 GDM.

Results: Post-partum, we found significantly increased levels of lipoperoxides (LPO) (P≤0.001) and catalase (P≤0.001) and significantly decreased glutathione peroxidase (GPX) (P=0.003) in both groups. Additionally, cases had lower levels of glutathione transferase (GST) (P=0.003) and controls had lower levels of superoxide dismutase (SOD) (P≤0.001). Multiple regression analyses were performed to evaluate the influence of clinical and metabolic variables on post-partum status. The levels of post-partum oxidative stress were significantly related in the GDM group. Significantly increased levels of carbonyl protein (p≤0.05) and LPO (p<0.05) together with reduced antioxidant enzyme activities of SOD (p≤0.05) and catalase (p≤0.05) were noted in GDM placenta.

Conclusions: We conclude that increased oxidative stress and reduction in antioxidant defence mechanisms occur in the circulation and placenta of women with GDM. Since these imbalances can lead to maternal complications, these variables need to be monitored carefully during GDM pregnancies.

Keywords: gestational diabetes mellitus, oxidative stress markers, antioxidants, placenta.