Associations between the thyroid panel and serum protein concentrations across pregnancy.

Establishing any characteristic associations between the serum parameters of thyroid function and serum proteins in pregnancy may aid in elucidating the role of the thyroid gland in the regulation of pregnancy-specific metabolic processes and in selecting candidate biomarkers for use in their clinical assessment. Concentrations of thyroid stimulating hormone (TSH), free tri-iodothyronine (fT3) and free thyroxine (fT4), six electrophoretically separated protein fractions (albumin, alpha-1-, alpha2-, beta-1-, beta-2- and gamma-globulins), representative proteins-albumin (ALB), transferrin (TRF), alpha-2-macroglobulin (AMG) and ceruloplasmin (CER) were measured in 136 serum samples from 65 women in their consecutive trimesters of pregnancy. The concentrations of TSH, fT4 and fT3 were significantly correlated (p < 0.05) with the concentrations of the albumin, alpha-2- and beta-1 globulin fractions. Significant correlations (p < 0.05) which were positive between fT4 and ALB and negative between fT4 and TRF were established throughout pregnancy. Significant negative correlations (p < 0.05) were demonstrated for fT3 with alpha-2-globulin, AMG and CER. Changes in the serum concentrations of thyroid hormones seen between the trimesters were found to correlate with the concentrations of high-abundance serum proteins. Opposite directions of correlations between fT4 and ALB and fT4 and TRF observed throughout pregnancy may indicate the shared biological role of these parameters in maintaining maternal homeostasis and they suggest their potential use in the clinic as a simple biomarker panel. A negative correlation of fT3 with CER in the second trimester possibly reflects their involvement in the active regulation of metabolic processes.

Can variability of serum electrophoretic fractions during pregnancy provide knowledge about maternal and fetal health.

AIM: Characteristics of variability of concentrations total protein and its electrophoretic fractions in serum of healthy pregnant women between successive trimesters and post-partum for initial classification of proteins involved in specific metabolic processes associated with pregnancy. METHODS: Total serum protein concentrations were measured by biuret method and serum protein fractions were electrophoretically separated in 166 serum samples collected from healthy pregnant women in three trimesters of pregnancy (1st, n = 55; 2nd, n = 42; 3rd, n = 39) and in post-partum (n = 30), and in 20 samples from nonpregnant controls. RESULTS: Across pregnancy, there were gradual, but occurring at different rates, decreases over time in serum total protein, albumin and gamma globulins compared to controls (P < 0.05). In 1st trimester, serum concentrations of total protein, albumin and gamma globulins were <10% lower than in nonpregnant state, with further decreases in 2nd and 3rd trimesters and in post-partum. The concentrations of alpha-1-, alpha-2-, beta-1- and beta-2-globulins were elevated compared to controls (P < 0.05) with different dynamics of change and with the highest percentage increase for alpha-1-globulin. CONCLUSION: Pregnancy-associated alterations in the serum concentrations of total protein and in its individual electrophoretic protein fractions in each trimester of pregnancy and differences versus normal ranges in nonpregnant healthy females could be a simple screening method for classification useful laboratory parameters that help obstetricians and gynecologists to make multidirectional judgments about the state of health of pregnant women.