Impact of gestational diabetes on lipid profiling and indices of oxidative stress in maternal and cord plasma

OBJECTIVE: To study the effect of gestational diabetes mellitus (GDM) on indices of oxidative stress and lipid profiles in maternal and cord blood samples.

METHODS: Blood samples were collected from 40 normal pregnant women and 46 women with GDM during the period 1998 through to 1999 at the Armed Forces Hospital, Riyadh, Kingdom of Saudi Arabia. The GDM patients were subdivided into 2 groups: patients receiving insulin treatment (GDM-I, N=19) and patients under control diet (GDM-D, N=27). Plasma a- and y-tocopherols were estimated by high-performance liquid chromatography, whereas malondialdehyde (MDA) was analyzed by fluorometry. Serum lipids (low density lipoprotein, high density lipoprotein, total cholesterol, triglycerides, and total lipids) were determined by enzymatic colorimetry using automated clinical analyzer.

RESULTS: The results of lipid profiles in maternal serum showed no significant difference between GDM patients and controls; however, all the lipid constituents except total cholesterol were significantly reduced in the cord blood of GDM patients as compared to control subjects. a-tocopherol levels in the maternal plasma were not significantly different among the 3 groups, whereas, cord plasma a-tocopherol was significantly decreased in both GDM-D and GDM-I. Maternal y-tocopherol was found to be significantly increased in GDM-D and only insignificantly increased in GDM-I, but the cord y-tocopherol showed no appreciable changes. The level of MDA was 3-fold higher in maternal plasma as compared to cord plasma. However, neither the maternal plasma nor cord plasma showed significant differences in MDA levels between GDM patients and normal pregnant women.

CONCLUSION: A significant depletion of a-tocopherol in the cord blood of GDM patients is indicative of a possible oxidative stress in their fetuses. Further studies are warranted to examine a wider range of biochemical parameters to evaluate the potential risks of oxidative damage.