Plasma Total Antioxidant Capacity and Carbonylated Proteins Are Increased in Pregnant Women with Severe COVID-19.

Oxidative stress (OS) induced by SARS-CoV-2 infection may play an important role in COVID-19 complications. However, information on oxidative damage in pregnant women with COVID-19 is limited. OBJECTIVE: We aimed to compare lipid and protein oxidative damage and total antioxidant capacity (TAC) between pregnant women with severe and non-severe COVID-19. METHODS: We studied a consecutive prospective cohort of patients admitted to the obstetrics emergency department. All women positive for SARS-CoV-2 infection by reverse transcription-polymerase chain reaction (RT-qPCR) were included. Clinical data were collected and blood samples were obtained at hospital admission. Plasma OS markers, malondialdehyde (MDA), carbonylated proteins (CP), and TAC; angiogenic markers, fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF); and renin-angiotensin system (RAS) markers, angiotensin-converting enzyme 2 (ACE-2) and angiotensin-II (ANG-II) were measured. Correlation between OS, angiogenic, and RAS was evaluated. RESULTS: In total, 57 pregnant women with COVID-19 were included, 17 (28.9%) of which had severe COVID-19; there were 3 (5.30%) maternal deaths. Pregnant women with severe COVID-19 had higher levels of carbonylated proteins (5782 pmol vs. 6651 pmol; p = 0.024) and total antioxidant capacity (40.1 pmol vs. 56.1 pmol; p = 0.001) than women with non-severe COVID-19. TAC was negatively correlated with ANG-II (p < 0.0001) and MDA levels (p < 0.0001) and positively with the sFlt-1/PlGF ratio (p = 0.027). CONCLUSIONS: In pregnant women, severe COVID-19 is associated with an increase in protein oxidative damage and total antioxidant capacity as a possible counterregulatory mechanism.

Novel Ratio Soluble Fms-like Tyrosine Kinase-1/Angiotensin-II (sFlt-1/ANG-II) in Pregnant Women Is Associated with Critical Illness in COVID-19.

BACKGROUND: In healthy pregnancies, components of the Renin-Angiotensin system (RAS) are present in the placental villi and contribute to invasion, migration, and angiogenesis. At the same time, soluble fms-like tyrosine kinase 1 (sFlt-1) production is induced after binding of ANG-II to its receptor (AT-1R) in response to hypoxia. As RAS plays an essential role in the pathogenesis of COVID-19, we hypothesized that angiogenic marker (sFlt-1) and RAS components (ANG-II and ACE-2) may be related to adverse outcomes in pregnant women with COVID-19; Methods: Prospective cohort study. Primary outcome was severe pneumonia. Secondary outcomes were ICU admission, intubation, sepsis, and death. Spearman's Rho test was used to analyze the correlation between sFlt-1 and ANG-II levels. The sFlt-1/ANG-II ratio was determined and the association with each adverse outcome was explored by logistic regression analysis and the prediction was assessed using receiver-operating-curve (ROC); Results: Among 80 pregnant women with COVID-19, the sFlt-1/ANG-II ratio was associated with an increased probability of severe pneumonia (odds ratio [OR]: 1.31; p = 0.003), ICU admission (OR: 1.05; p = 0.007); intubation (OR: 1.09; p = 0.008); sepsis (OR: 1.04; p = 0.008); and death (OR: 1.04; p = 0.018); Conclusion: sFlt-1/ANG-II ratio is a good predictor of adverse events such as pneumonia, ICU admission, intubation, sepsis, and death in pregnant women with COVID-19.

SARS-CoV-2 colonization of maternal and fetal cells of the human placenta promotes alteration of local renin-angiotensin system.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection appears to increase the risk of adverse pregnancy outcomes, such as pre-eclampsia in pregnant women. The mechanism(s) by which this occurs remains unclear. METHODS: We investigated the pathophysiology of SARS-CoV-2 at maternal-fetal interface in pregnant women who tested positive for the virus using RNA in situ hybridization (viral RNA), immunohistochemistry, and hematoxylin and eosin staining. To investigate whether viral infection alters the renin angiotensin system (RAS) in placenta, which controls blood pressure, we treated human trophoblasts with recombinant spike protein or a live modified virus with a vesicular stomatitis viral backbone expressing spike protein (VSV-S). FINDINGS: Viral colonization was highest in maternal decidua, fetal trophoblasts, Hofbauer cells, and in placentas delivered prematurely. We localized SARS-CoV-2 to cells expressing angiotensin-converting enzyme 2 (ACE2) and demonstrate that infected placentas had significantly reduced ACE2. In response to both spike protein and VSV-S, cellular ACE2 decreased although angiotensin II receptor type 1 (AT1R) increased with concomitant increase in soluble fms-like tyrosine kinase-1 (sFlt1). Viral infection decreased pro-angiogenic factors, AT2R, and placental growth factor, which competitively binds to sFlt1. Sera from infected pregnant women had elevated levels of sFlt1 and angiotensin II type 1-receptor autoantibodies prior to delivery, both signatory markers of pre-eclampsia. CONCLUSIONS: SARS-CoV-2 colonizes ACE2-expressing maternal and fetal cells in the placenta. Infection in pregnant women correlates with alteration of placental RAS. As RAS regulates blood pressure, SARS-CoV-2 infection may thus increase adverse hemodynamic outcomes, such as pre-eclampsia in pregnant women. FUNDING: NIH/NICHD grants R01 HD091218 and 3R01HD091218-04S1 (RADx-UP Supplement).

Pre-eclampsia-like syndrome induced by severe COVID-19: a prospective observational study.

OBJECTIVES: To investigate the incidence of clinical, ultrasonographic and biochemical findings related to pre-eclampsia (PE) in pregnancies with COVID-19, and to assess their accuracy to differentiate between PE and the PE-like features associated with COVID-19. DESIGN: A prospective, observational study. SETTING: Tertiary referral hospital. PARTICIPANTS: Singleton pregnancies with COVID-19 at >20+0  weeks. METHODS: Forty-two consecutive pregnancies were recruited and classified into two groups: severe and non-severe COVID-19, according to the occurrence of severe pneumonia. Uterine artery pulsatility index (UtAPI) and angiogenic factors (soluble fms-like tyrosine kinase-1/placental growth factor [sFlt-1/PlGF]) were assessed in women with suspected PE. MAIN OUTCOME MEASURES: Incidence of signs and symptoms related to PE, such as hypertension, proteinuria, thrombocytopenia, elevated liver enzymes, abnormal UtAPI and increased sFlt-1/PlGF. RESULTS: Thirty-four cases were classified as non-severe and 8 as severe COVID-19. Five (11.9%) women presented signs and symptoms of PE, all five being among the severe COVID-19 cases (62.5%). However, abnormal sFlt-1/PlGF and UtAPI could only be demonstrated in one case. One case remained pregnant after recovery from severe pneumonia and had a spontaneous resolution of the PE-like syndrome. CONCLUSIONS: Pregnant women with severe COVID-19 can develop a PE-like syndrome that might be distinguished from actual PE by sFlt-1/PlGF, LDH and UtAPI assessment. Healthcare providers should be aware of its existence and monitor pregnancies with suspected pre-eclampsia with caution. TWEETABLE ABSTRACT: This study shows that a pre-eclampsia-like syndrome could be present in some pregnancies with severe COVID-19.