Maternal Amino Acid Status in Severe Preeclampsia: A Cross-Sectional Study

Abstract

Introduction: Preeclampsia has been one of the leading causes of maternal death in Indonesia. It is postulated that its relationship with oxidative stress may be the underlying pathology of the disease. Nutrients and amino acids have been suggested as a scavenger for oxygen-free radicals. No previous study regarding the amino acid status in preeclampsia has been conducted in women in Indonesia. Methods: This was a cross-sectional study of a total of 64 pregnant women, 30 with normal pregnancy and 34 with severe preeclampsia. Data were obtained in Cipto Mangunkusumo National Referral Hospital in Jakarta from July to December 2020. Maternal blood samples were taken during or soon after delivery. Amino acid levels were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Bivariate analysis was then performed. Results: We identified 19 different levels of amino acids in this study. Four amino acids that were elevated in the preeclampsia group were phenylalanine, serine, glycine, and glutamate. Serine (331.55 vs. 287.43; p = 0.03), glycine (183.3 vs. 234.35, p = 0.03), and glutamate levels (102.23 vs. 160.70, p = 0.000) were higher in preeclamptic patients. While in the essential amino acids group, phenylalanine levels (71.5 vs. 85.5, p = 0.023) were higher, and methionine levels (16.3 vs. 12.9, p = 0.022) were lower in preeclamptic patients. Conclusions: These findings suggest that severe preeclampsia had differences in concentration of some amino acids compared to normal pregnancy. Glutamate and methionine were associated with preeclampsia. Furthermore, a more detailed study regarding amino acids in the pathomechanism of preeclampsia is suggested.

Nuclear magnetic resonance spectroscopy based investigation of placenta and serum metabolic signatures in an L-NAME-induced preeclampsia rat model

“…These amino acids include both non-essential ones, such as glycine, tyrosine, and creatine, and essential ones like phenylalanine, isoleucine, tryptophan, and lysine. These altered metabolites are primarily involved in the glycine/serine/threonine metabolism pathway and the phenylalanine/tyrosine/tryptophan biosynthesis pathway, indicating a disrupted amino acid metabolism previously observed in PE patients(Prameswari et al 2022). The elevated nitrogen demand by the placenta during EOPE corresponds to increased oxidative stress levels and a greater need for maternal placental vascular remodeling, which may account for the higher levels of glycine and tyrosine detected in maternal blood(Liu et al 2019).…”

Predicting the onset of preeclampsia by longitudinal monitoring of metabolic changes throughout pregnancy with Raman spectroscopy

“…An increase in glycine in preeclamptic patients has been associated with glycolysis defects in the placenta and correlates well with the increase in glucose observed in our results (Figure 3e). 50 This suggests that AAs have a complex interplay in pregnancy both necessary for fetal growth but also contribute to inflammation and dysregulation of energy pathway. In our previous work focused on Raman spectral analysis of pregnant patient plasma samples who had preterm birth, we also observed similar tends in AAs 28 .…”

“…The Raman peaks, the tentative metabolic assignment, and the corresponding vibrational modes are listed in Table 2 confirmed with literature findings. 33 , 34 , 35 , 36 , 37 In assigning our peaks, we used a three step approach: (1) we referred to the cited literature in Table 2 , which are highly cited and well‐established Raman reference papers 33 , 34 , 35 , 36 , 37 ; (2) we referred to papers focused on metabolism in pregnancy disorders (see references 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ) to ensure that the metabolites assigned are relevant in pregnancy; and (3) we also referred to papers that highlight metabolites present in blood and blood components. 54 , 55 This three step approach gave us confidence in our tentative peak assignments, and the metabolic pathways that have resulted from these assignments.…”

“…(2) we referred to papers focused on metabolism in pregnancy disorders (see references [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53] to ensure that the metabolites assigned are relevant in pregnancy; and (3) we also referred to papers that highlight metabolites present in blood and blood components. 54,55 This three step approach gave us confidence in our tentative peak assignments, and the metabolic pathways that have resulted from these assignments.…”