Evaluation of plasma ascorbate, erythrocyte plasma membrane redox system and ascorbate free radical reductase system in different trimesters Of normal pregnancy

Background: Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Normal pregnancy is associated with high metabolic demand and elevated requirement for tissue oxygen. There is increased production of reactive oxygen species and increased oxidative stress. Plasma Ascorbate, Erythrocyte Plasma Membrane Redox System and Ascorbate Free Radical Reductase System are some of the antioxidants. Objectives: In our study we wanted to evaluate the change in these antioxidents’ levels in different trimester of normal pregnancy in respect to non pregnant women. Methods: The methodology includes measurement of PMRS activity by Avron and Savit’s procedure; Vitamin C by Teitz and AFR reductase activity by guidline of May et al. Results: In respect to control group there was no significant difference in 1st trimester and 2nd trimester, but there was significant difference in 3rd trimester in PMRS values. Vitamin C levels showed no significant difference in 1st trimester but there was significant difference in 2nd and 3rd trimester compared to controls. In respect to control group there was significant difference with 1st,2nd and 3rd trimester in AFR Reductase activity. On correlation study NADH Values ( AFR reductase activity was measured in terms of NADH oxidase) had negative correlation with PMRS and positive correlation with Vitamin C in both non pregnant and pregnant women. Conclusion: In present study it can be concluded that as the trimesters progress there is increase in PMRS level, AFR activity and decrease in Vitamin C level with increase in oxidative stress.