Lipid profile and lipid oxidative modification parameters in the first trimester of high- risk pregnancies - possibilities for preeclampsia prediction.

OBJECTIVES: The goal of this study was to investigate metabolic changes in lipids and oxidative stress parameters in the first trimester of pregnancy with the more specific aim of estimating the significance and strength of researched parameters in the prediction of preeclampsia. DESIGN AND METHODS: The study included 87 high-risk pregnant (HRG) female subjects, 14 with developed preeclampsia (PEC) and 43 healthy pregnant female subjects matched for gestational age (CG). Thiobarbituric acid-reactive substances (TBARS) concentration, lipid hydroperoxides (LOOH), pro-oxidant antioxidant balance (PAB) and total oxidative status (TOS) were measured as oxidative stress markers, while total antioxidant capacity (TAC) was measured as an antioxidative defense parameter. The Atherogenic Index of Plasma (AIP) was calculated as the base 10 logarithm of the ratio of the plasma concentration of triglycerides (TG) to the plasma concentration of high-density lipoprotein cholesterol (HDL-C), with each concentration expressed in mmol/L. RESULTS: The results have shown that lipid indices, especially AIP, were significantly higher in the first trimester of HRG (p < 0.001) and PEC (p < 0.001). Oxidative stress parameters were significantlly higher, while TAC was significantly lower in HRG vs. CG [0.7 ± 0.15 vs 1.1 ± 0.16; (p < 0.001)] and in PEC [0.6 ± 0.12 vs 1.1 ± 0.16; (p < 0.001)] vs. CG. Also, in the HRG, results have shown an independent association of AIP with the preeclampsia development (p < 0.05), while placental growth factor did not show the expected level of significance (p = 0.648). Analysis of the Receiver Operating Characteristics (ROC) curves indicated that certain parameters included in the research model have very good diagnostic accuracy for preeclampsia (AUC = 0.856). CONCLUSIONS: AIP is associated with high-risk pregnancies. Furthermore, our results firmly underscored AIP as a potential marker for preeclampsia prediction.

Rapid ion-exchange method for the determination of 3-methylhistidine in rat urine and skeletal muscle.

A method for the determination of 3-methylhistidine using an automatic amino acid analyser has been developed. A single column system with lithium buffer (pH 3.950, 0.500 mol/l lithium and 0.067 mol/l citrate) was used for elution. The standard amino acid mixture of basic amino acids and some dipeptides usually present in physiological fluids was analysed for the development of the method. 3-Methylhistidine eluted in 46.7 +/- 0.049 min and the peak area coefficient of variation for the same sample was 1.07%. As 3-methylhistidine is completely resolved from the other basic amino acids and some dipeptides (anserine and carnosine), this method is suitable for the analysis of urine and muscle extracts as well as skeletal muscle protein hydrolysates where this amino acid is present in much lower concentrations than other amino acids.