Circular RNA expression profiles and circRNA-miRNA-mRNA crosstalk in pre-eclamptic placenta / 中华妇产科杂志

Objective: To identify the expression profile of circular RNA (circRNA) in placenta of pre-eclampsia (PE) pregnant women by high-throughput sequencing, and to construct the circRNA-microRNA (miRNA)-messenger RNA (mRNA) interaction network, so as to reveal the related pathways and regulatory mechanisms of PE. Methods: The clinical data and placentas of 42 women with PE (PE group) and 30 normal pregnant women (control group) who delivered in West China Second University Hospital from November 2019 to June 2021 were collected. (1) High-throughput sequencing was used to establish the differentially expressed circRNA profiles in placental tissues of 5 pairs of PE group and the control group. (2) Real-time quantitative PCR (qRT-PCR) was used to verify the expression levels of 6 differentially expressed circRNAs in placental tissues of PE group and control group. (3) Bioinformatics analysis was used to predict the target miRNA and analyze the co-expressed mRNA to construct a competitive endogenous RNA (ceRNA) network. The differentially expressed circRNAs were analyzed by Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathways. (4) Logistic regression analysis, Pearson correlation and Kendall's tau-b correlation analysis were used to test the correlation between the three differentially expressed circRNAs and the risk of PE and clinical characteristics. (5) circRNA_05393 was selected for subsequent functional study. Small interfering RNA (siRNA) and overexpression plasmid were used to knock down or increase the expression level of circRNA_05393 in trophoblast cell line HTR-8/SVneo cells, respectively. Transwell assay was used to detect the migration and invasion ability of the trophoblasts in vitro. Cell counting kit-8 assay was used to detect the proliferation ability of the trophoblasts. Results: (1) Seventy-two differentially expressed circRNAs were identified by high-throughput sequencing, of which 35 were up-regulated and 37 were down-regulated. (2) qRT-PCR showed that compared with the control group, circRNA_00673 (1.306±0.168 vs 2.059±0.242; t=2.356, P=0.021) and circRNA_07796 (1.275±0.232 vs 1.954±0.230; t=2.018, P=0.047) were significantly increased, while circRNA_05393 (1.846±0.377 vs 0.790±0.094; t=3.138, P=0.002) was significantly decreased. (3) The circRNA-miRNA-mRNA interaction network contained 3 circRNAs, 8 miRNAs and 53 mRNAs. GO functional annotation analysis showed that the biological process was mainly enriched in iron ion homeostasis, membrane depolarization during action potential and neuronal action potential. In terms of cellular components, they were mainly enriched in cytoskeleton and membrane components. In terms of molecular function, they were mainly enriched in the activity of voltage-gated sodium channel and basic amino acid transmembrane transporter. KEGG pathway enrichment analysis showed that mRNAs in the interaction network were mainly enriched in complement and coagulation cascade, glycine, serine and threonine metabolism, p53 signaling pathway and peroxisome proliferators-activated receptors (PPAR) signaling pathway. (4) Logistic regression analysis showed that down-regulation of circRNA_05393 expression was a risk factor for PE (OR=0.044, 95%CI: 0.003-0.596; P=0.019). Correlation analysis showed that circRNA_05393 was significantly correlated with systolic blood pressure and diastolic blood pressure in PE pregnant women (both P<0.05). (5) Knock down or overexpression of circRNA_05393 significantly reduced or increased the migration and invasion abilities of HTR-8/SVneo cells (all P<0.05), but had no significant effect on the ability of tube formation and proliferation (all P>0.05). Conclusions: The construction of circRNA expression profile in placenta and the exploration of circRNA-miRNA-mRNA interaction network provide the possibility to reveal the regulatory mechanism of specific circRNA involved in PE. Inhibition of circRNA_05393 may induce the progression of PE by reducing the migration and invasion of trophoblasts.

Effects of vitamin D-induced supernatant of placental explants from preeclamptic women on oxidative stress and nitric oxide bioavailability in human umbilical vein endothelial cells

The study evaluated the effect of the supernatant of placental explants from preeclamptic (PE) and normotensive (NT) pregnant women after tissue treatment with or without vitamin D (VD) on oxidative stress and nitric oxide (NO) bioavailability in human umbilical vein endothelial cells (HUVEC). Placental explants were prepared from eight NT and eight PE women, and supernatants were obtained after incubation with or without hydrogen peroxide (H2O2) and/or VD. HUVEC were cultured for 24 h with supernatants, and the following parameters were analyzed in HUVEC cultures: NO, nitrate (NO3-), and nitrite (NO2-) levels, lipid peroxidation, and intracellular reactive oxygen species (ROS). Results showed that the production of NO3-, NO2-, malondialdehyde (MDA), and ROS were significantly higher in HUVEC treated with explant supernatant from PE compared to NT pregnant women, while the supernatant of PE explants treated with VD led to a decrease in these parameters. A significantly high production of NO was detected in HUVEC cultured with control supernatant of NT group, and in cultures treated with supernatant of PE explants treated with VD. Taken together, these results demonstrated that cultures of placental explants from PE women with VD treatment generated a supernatant that decreased oxidative stress and increased the bioavailability of NO in endothelial cells.

Differential expression of microRNA-411 and 376c is associated with hypertension in pregnancy

Preeclampsia is a major reason of morbidity and mortality in pregnant women and perinatal fetus. Hence, it is of prime importance that diagnostic markers are defined to predict chances of preeclampsia in pregnant women. It has been previously shown that microRNA (miRNA)-376c expression is decreased in the placenta of preeclampsia patients at term. Even though this decrease was not mimicked in the placenta at the pre-term stage, miR-376c expression was decreased in the plasma of these patients as early as the second trimester. Plasma and placenta specimens were obtained from pregnant women having unifetal gestation undergoing perinatal care between January 2014 and December 2016 (n=49). Early trimester placentas were collected from patients undergoing terminated pregnancies through dilation and curettage procedure. Our results showed that in addition to miR-376c, miR-441 levels were decreased in the placenta of preeclampsia patients, and this decrease occurred both at pre-term and at term. This decrease is also mimicked in the plasma levels at both early and late weeks of pregnancy, highlighting that miR-441 levels can serve as a diagnostic marker of risk of preeclampsia in pregnant women. Overexpression of the miR-441, as well as miR-376c, promoted cell viability, migration, and invasion in the human immortalized cytotrophoblast cell line HTR8/SVneo, indicating that their decrease in pregnant women would result in anomalous apoptosis and functional imbalance resulting in premature abortion and other complications. MiR-441 level can thus potentially serve as diagnostic marker of preeclampsia in pregnant women.

Expression of endothelin-1 and Ki-67 in normotensive and severe preeclamptic placentas / Expresión de endotelina-1 y Ki-67 en placentas normotensas y preeclampsia severa

SUMMARY: Severe preeclampsia (HELLP syndrome) is a life-threatening pregnancy complication, usually a severe form of preeclampsia. In this study, we aimed to examine histopathologic changes and Endothelin-1 and KI-67 expression levels by immunohistochemical methods in severe preeclamptic placentas. Severe preeclampsia and obstetric characteristics and biochemical and hematological characteristics of healthy subjects were compared. Placenta sections were stained with hematoxylin-eosin for histopathological examination. In the histopathological examination of severe preeclamptic placenta, degeneration in synaptic and cytotrophoblastic cells, increase in insidious knots, fibrinoid necrosis, degeneration in endothelial cells, calcification and hyaline villous stains were observed. In the severe preeclampsia group, Ki-67 expression increased in decidua cells and inflammatory cells, while endothelial cells in the vessel wall and inflammatory cells in the villus and intervillous spaces increased. It is thought that angiogenetic and cellular proliferation is induced in a co-ordinated manner and significantly influences fetal development.

RESUMEN: La preeclampsia severa (síndrome de HELLP) es una complicación del embarazo potencialmente mortal, generalmente una forma grave de preeclampsia. En este estudio, nuestro objetivo fue examinar los cambios histopatológicos y los niveles de expresión de Endotelina-1 y Ki-67 mediante métodos inmunohistoquímicos en placentas preeclámpsicas graves. Se compararon la preeclampsia grave y las características obstétricas, además de las características bioquímicas y hematológicas de pacientes sanas. Las secciones de placenta se tiñeron con hematoxilina-eosina para examen histopatológico. En el examen histopatológico de placenta preeclampsia severa, se observó la degeneración en células sinápticas y citotrofoblásticas, un aumento de nudos insidiosos, necrosis fibrinoide, degeneración en las células endoteliales,calcificación y manchas vellosas hialinas. En el grupo de preeclampsia grave, la expresión de Ki-67 aumentó en células deciduas y células inflamatorias, mientras que las células endoteliales en la pared del vaso, y las células inflamatorias en las vellosidades y los espacios intervellosos aumentaron. Se cree que la proliferación angiogenética y celular se induce de forma coordinada y que influye significativamente en el desarrollo fetal.

Interleukin-6 contributes to myocardial damage in pregnant rats with reduced uterine perfusion pressure

Preeclampsia is one of the most frequent and difficult illnesses in pregnancy, which jeopardizes both mother and fetus. There are several diagnostic criteria for preeclampsia. However, the preeclampsia-associated myocardial damage has not been described. In this study, we employed reduced uterine perfusion pressure (RUPP) to generate a rat model of preeclampsia for the evaluation of myocardial damage in late-gestation rats. The expressions of cardiac injury markers were analyzed by immunohistochemistry and ELISA. The arterial pressure and myocardial tissue velocities were also measured. The role of interleukin (IL)-6 in RUPP-associated myocardial damage was further explored. The results showed that RUPP rats had significant myocardial damage, as demonstrated by the high expressions of myoglobin, creatine kinase isoenzyme, cardiac troponin I, and brain natriuretic peptide. In addition, RUPP increased the mean arterial pressure and the early transmitral flow velocity to mitral annulus early diastolic velocity ratio (E/Ea). Furthermore, IL-6 deteriorated these abnormalities, whereas inhibition of IL-6 significantly relieved them. In conclusion, our study demonstrated that RUPP rats displayed myocardial damage in an IL-6-dependent manner.

The Proteomic Analysis of Human Placenta with Pre-eclampsia and Normal Pregnancy

Preeclampsia is one of the most important and complexed disorders for women's health. Searching for novel proteins as biomarkers to reveal pathogenesis, proteomic approaches using 2DE has become a valuable tool to understanding of preeclampsia. To analyze the proteomic profiling of preclamptic placenta compared to that of normal pregnancy for better understanding of pathogenesis in preeclampsia, placentas from each group were handled by use of proteomics approach using 2DE combined with MALDI-TOF-MS. The 20 spots of showing differences were analysed and identified. Among differentially expressed protein spots Hsp 27 and Hsp 70 were selected for validation using Western blot analysis. In preeclamptic placenta 9 differentially expressed proteins were down-regulated with Hsp 70, serum albumin crystal structure chain A, lamin B2, cytokeratin 18, actin cytoplasmic, alpha fibrinogen precursor, septin 2, dihydrolipoamide branched chain transacylase E2 and firbrinogen beta chain. The 11 up-regulated proteins were fibrinogen gamma, cardiac muscle alpha actin proprotein, cytokeratin 8, calumenin, fibrinogen fragment D, F-actin capping protein alpha-1 subunit, Hsp 27, Hsp 40, annexin A4, enoyl-CoA delta isomerase and programmed cell death protein 6. The western blot analysis for validation also showed significant up-regulation of Hsp 27 and down-regulation of Hsp 70 in the placental tissues with preeclmaptic pregnancies. This proteomic profiling of placenta using 2DE in preeclampsia successfully identifies various proteins involved in apoptosis, mitochondrial dysfunction, as well as three Hsps with altered expression, which might play a important role for the understanding of pathogenesis in preeclampsia.

Utilidad de los fluidos en pacientes con pre-eclampsia/eclampsia: evidencia / Utility fluids in patients with pre-eclampsia-eclampsia: evidence

La preeclampsia/eclampsia se caracteriza por presión arterial elevada durante el embarazo, presentándose en cerca del 8-10% de todos los embarazos. En la mujer embarazada normalmente hay un aumento del volumen plasmático, sin embargo en preeclampsia-eclampsia usualmente dicho volumen esta disminuido. Esta disminución del volumen plasmático ha llevado a la idea de que hay que administrar fluidos para mantener la estabilidad hemodinámica materna...

Role of nitric oxide, angiogenic growth factors and biochemical analysis in preeclampsia.

Preeclampsia, a pregnancy-related hypertensive disorder, is one of the leading causes of fetal and maternal mortality and morbidity globally. Angiogenic growth factors, including vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) are involved in the generation of new blood vessels required for placental development and physiological functions, while nitric oxide (NO) acts as vasodilator and also plays a role in angiogenesis. The objective of this study was to evaluate the role of NO, angiogenic growth factors (VEGF and PIGF) and other biochemical parameters in the development of preeclampsia among pregnant mothers. A complete clinical history, including anthropometric measurements and biochemical investigations, including renal function tests, liver function tests and lipid profile were performed among twenty preeclampsia patients aged 19 to 32 yrs. Results were compared with age-matched normotensive pregnant mothers. The body weight, body mass index (BMI), blood pressure, concentrations of urea, uric acid and triglyceride and activities of transaminase enzymes (aspartate transaminase, AST and alanine transaminase, ALT) in serum were significantly higher (p<0.05) than normotensive subjects. Serum concentrations of VEGF, PlGF and NO were significantly decreased (p<0.005) in preeclamptic patients. NO was found negatively correlated with body weight (r = -0.369, p<0.05), systolic blood pressure (r = -0.822, p<0.005), diastolic blood pressure (r = -0.714, p<0.005) and was positively correlated with VEGF (r = 0.464, p<0.005) and PlGF (r = 0.546, p<0.005). VEGF and PlGF showed significant (p<0.005) negative correlation with systolic and diastolic blood pressure and PlGF was significantly correlated with triglyceride (r = -0.379). However, no significant correlation was observed between the VEGF and PlGF. In conclusion, the results indicated that body weight, triglyceride, angiogenic growth factors and NO might associate with preeclampsia development.

Pré-eclâmpsia: o que há de anômalo na placentação? / Preeclampsia: what is wrong with placentation

A pré-eclâmpsia (PE) constitui a principal causa de morte materna em diversos países do mundo e contribui significativamente para a prematuridade, o baixo peso fetal e o aumento da mortalidade neonatal. A placenta constitui o substrato anatômico etiopatogênico principal para a doença, inclusive em ambiente extra-uterino ou na ausência de embrião. O único tratamento efetivo para a PE consiste na interrupção da gravidez e remoção completa da placenta. Em muitos casos, esta medida precisa ser tomada prematuramente, visando garantir a vida da mãe, do bebê ou de ambos. Estudos clínicos, histológicos e laboratoriais demonstram alterações hemodinâmicas, histológicas, imunológicas e bioquímicas na placentação de mulheres portadoras de PE. Entender como essas alterações assumem proporções sistêmicas no organismo materno pode ser a chave para impedir a progressão abrupta e violenta da doença. Certamente, o entendimento de todo o processo fisiopatológico é necessário para qualquer proposta de predição, prevenção ou terapia que possa diminuir as altíssimas taxas de mortalidade atribuídas à PE.

Preeclampsia (PE) is the leading cause of maternal death in many countries worldwide and contributes significantly to prematurity, low fetal weight and increased neonatal mortality. The placenta seems to be the main etiopathogenic anatomical substrate for the disease even in extra-uterine environment or in the absence of the embryo. The only effective treatment for PE is the pregnancy interruption and complete placenta removal. In many cases, this action needs to be taken prematurely in order to ensure the life of the mother, baby or both. Clinical, histological and laboratory have shown hemodynamic, histological, immunological and biochemical abnormalities in placentation in women with PE. Understanding how these changes take on systemic proportions in the mother may be the key to prevent the abrupt progression of the disease. Indeed, an understanding of all physiological and the alterations in PE process is required for any action of prediction, prevention or therapy that can reduce the extremely high rates of mortality associated to PE.

Preeclampsia: la evolución diagnóstica desde la genómica y la proteómica / Preeclampsia: diagnostic evolution from genomics and proteomics

La preeclampsia se define como la presencia de hipertensión arterial evidenciada con dos lecturas de presión arterial > 140/90 (presión arterial sistólica > 140 mmHg o diastólica > 90 mmHg) y proteinuria superior a 0,3 g/día después de la vigésima semana de embarazo en pacientes anteriormente normotensas. Aún se desconoce la verdadera causa, aunque existen algunas teorías que indican que la combinación de varios factores ambientales, genéticos e inmunológicos puede aumentar la susceptibilidad. La genómica y proteómica han venido proporcionando herramientas para la comprensión y diagnóstico de nuevos biomarcadores que apunten hacia novedosos avances en el diagnóstico, la prevención y el tratamiento de dicha patología.

Preeclampsia was defined as the presence of hypertension evidenced two blood pressure readings > 140/90 (systolic blood pressure > 140 mmHg or diastolic > 90 mmHg) and proteinuria greater than 0.3 g/day after the twentieth week pregnancy in previously normotensive patients. Still the real cause is unknown, although there are some theories that suggest that a combination of environmental factors, genetic and immunological may increase susceptibility. Genomics and proteomics have been providing necessary progress in the understanding and diagnosis of new biomarkers that point to novel advances in the diagnosis, prevention and treatment of this disease.

Expression and Localization of COMMD1 Proteins in Human Placentas from Women with Preeclampsia

PURPOSE: Recently, COMMD1 has been identified as a novel interactor and regulator of hypoxia-inducible factor-1 and nuclear factor kappa B transcriptional activity. The goal of this study was to determine the difference of COMMD1 expression in the placentas of women with normal and preeclamptic (PE) pregnancies. MATERIALS AND METHODS: Immnoperoxidase and immunofluorescent staining for COMMD1 was performed on nine normal and nine severe PE placental tissues, and COMMD1 mRNA expression was quantified by quantitative reverse transcription polymerase chain reaction. RESULTS: The expression of mRNA of COMMD1 was significantly higher in the study group than in the control group. The immunoreactivity was higher especially in the syncytiotrophoblast of PE placentas than in the control group. CONCLUSION: This study demonstrated increased placental COMMD1 expression in women with severe preeclampsia compared to that found in women with normal pregnancies, and this finding might contribute to a better understanding of the pathophysiology of preeclampsia.

El sistema renina angiotensina y el estrés oxidativo en un modelo experimental de preeclampsia en ratas / The renin angiotensin system and the oxidative stress in a animal model of preeclampsia in rats

La preeclampsia es un síndrome exclusivo de la gestación humana y responsable de una alta morbimortalidad perinatal, cuyas manifestaciones incluyen: hipertensión arterial, proteinuria y edema. Un mecanismo postulado en la fisiopatología de la preeclampsia, es la reducción de la perfusión placentaria y el desarrollo del síndrome clínico materno ocasionado por la liberación de factores placentarios que afectan la regulación de la presión arterial y la función renal. Uno de los factores que ocasiona el trastorno endotelial son las especies reactivas de oxígeno, el incremento de elementos vasoactivos, así como la disminución de agentes vasorelajantes como el óxido nítrico. Todas estas alteraciones vasculares conducen no sólo a la hipertensión sino también a la disfunción renal. Debido a la importancia del papel del óxido nítrico y su desregulación en la preeclampsia, en el presente trabajo se caracterizó un modelo experimental de preeclampsia que resulta de la inhibición de la síntesis de óxido nítrico mediante la administración de L-NAME a ratas preñadas y no preñadas. En el mismo se evaluó el estatus oxidativo y, el papel del sistema renina angiotensina en la contribución de la disfunción renal. Los resultados demuestran el papel primordial del óxido nítrico y su desregulación en este modelo de preeclampsia experimental. En efecto, se demostró que el tratamiento durante siete días con L-NAME incrementó la presión arterial media, aumentó la sensibilidad vascular, inhibió la actividad de la sintasa del óxido nítrico renal y redujo el guanilil monofosfato cíclico urinario. La disfunción endotelial renal en este modelo experimental se manifiesto por proteinuria, incremento de la creatinina plasmática, disminución de la excreción urinaria de sodio, potasio y creatinina, así como, evidencia morfológica de endoteliosis glomerular. Al caracterizar el papel de las enzimas antioxidantes renales se encontró una reducción significativa de la actividad de las mismas, y un incremento de la peroxidación lipídica asociada a una elevada concentración de agentes pro-oxidantes. Nuestro modelo experimental constituye una buena aproximación a la preeclampsia humana y no un efecto inespecífico del L-NAME, ya que aún cuando la inhibición crónica de la síntesis de óxido nítrico en ratas no preñadas induce un incremento de la presión arterial media, proteinuria, reducción de la actividad de la sintasa del óxido nítrico renal y de la excreción urinaria de guanilil monofosfato cíclico similar a las ratas preñadas, los efectos sobre la proteinuria, las acciones morfológicas renales, la excreción urinaria de sodio, potasio y creatinina, y sobre el sistema renina angiotensina son específicos de la preeclampsia experimental en ratas. Así, se demostró que en las ratas preñadas tratadas con L-NAME la actividad de la enzima convertidora de angiotensina plasmática, los niveles de renina plasmática, y la aldosterona amniótica se encuentran marcadamente disminuidos, cuando se comparan con las ratas preñadas normotensas. Estos hallazgos sugieren que la preeclampsia experimental se caracteriza por la supresión de los componentes circulantes del sistema renina angiotensina, que podrían ser responsables del desbalance entre los sistemas vasoconstrictores y vasodilatadores observados en la preeclampsia, así como de algunos de los signos de la preeclampsia, similar a lo que ocurre en la mujer embarazada hipertensa. Por otra parte, al evaluar la contribución del estrés oxidativo en el daño renal en la preeclampsia experimental, se demostró una disminución de la actividad de las enzimas antioxidantes renales. Asimismo, la disminución de la actividad de la glutatión peroxidasa plasmática y la tendencia a la reducción en la glutatión peroxidasa en el líquido amniótico, con el simultáneo incremento de los valores de las sustancias que reaccionan con el ácido tiobarbitúrico (TBARS) plasmático, sugiriéndose que la desregulación generalizada y renal está asociada a una baja protección oxidativa durante la preeclampsia, que favorece a la insuficiencia renal. El incremento temprano del estrés oxidativo placentario juega un papel fundamental en la disfunción endotelial generalizada y el daño renal en la preeclampsia. Debido a ello, nos planteamos que el tratamiento temprano con antioxidantes o con desacoplantes de la NAD (P) H oxidasa podría interrumpir el proceso de este síndrome. Efectivamente, el tratamiento crónico con un compuesto que mimetiza a la superóxido dismutasa, el tempol, o el desacoplante del ensamblaje de la NAD(P)H oxidasa (apocinina), fueron capaces de reducir significativamente la hipertensión inducida por el L-NAME. Igualmente, ambos compuestos fueron capaces de prevenir la proteinuria y la reducción de la actividad de las enzimas antioxidantes renales estudiadas. En conclusión, la preeclampsia experimental inducida por la inhibición crónica de la síntesis de óxido nítrico en ratas preñadas, reproduce los signos clásicos de la preeclampsia humana, y se acompaña de la desregulación del sistema renina angiotensina y de disfunción renal. Esto nos permite aseverar que este modelo experimental de preeclampsia constituye una buena aproximación a la preeclampsia humana. Se demuestra que el daño renal encontrado en este modelo experimental se asocia a una disminución de los mecanismos antioxidantes renales, que lleva a un incremento del estrés oxidativo, y a una reducción de la protección de la función renal. Estos resultados indican que la sobreproducción de especies reactivas de oxígeno tanto placentaria como renal, son causa fundamental de la disfunción endotelial generalizada y del daño renal. Finalmente, la inhibición del estrés oxidativo mediante el uso de agentes antioxidantes como el tempol o la apocinina, pudiese ser una de las posibles estrategias terapéuticas en el tratamiento de la hipertensión inducida por el embarazo humano y abre nuevos horizontes en el tratamiento de este síndrome.

HSP70 Expression and its Role in Preeclamptic Stress.

Preeclampsia, a hypertensive pregnancy-specific disorder, has long been analyzed for its association with cellular stress. It still remains one of the most serious complications of pregnancy. It is a multi-system disorder that affects maternal vascular function and fetal growth. The physiopathology of preeclampsia is still unclear, but an imbalance between reactive oxygen species (ROS) and antioxidants, appears to be an important contributing factor. Oxidative stress has been increasingly postulated as a major contributor to endothelial dysfunction in preeclampsia (PE). The ROS promotes lipid oxidation and are known to induce stress proteins, such as hemeoxygenase 1 (HO-1) and heat-shock protein 70 (HSP70). Embryonic and placental cells are highly sensitive to oxidative stress due to their proliferate nature. Endothelial cell dysfunction is suggested to be a part of wider maternal inflammatory reaction responsible for the clinical syndrome of preeclampsia. Part of the dysfunction in endothelial cell and trophoblast is attributed to oxidative stress developed during pregnancy. The disequilibrium in compensatory antioxidant control is proposed as a causative mechanism in the pathophysiology of preeclampsia. HSP70 acts as the secondary line of defense in systems with compromised antioxidant function. This article reviews the differential expression of HSP70 and the effect of mint-tea therapy to modulate preeclamptic oxidative damage.

Serum lipid levels in pregnancies complicated by preeclampsia / Concentrações séricas de lipídeos em gestações com complicações de pré-eclâmpsia

CONTEXT AND OBJECTIVE: Pre-eclampsia is a disorder that occurs only during pregnancy. Postpartum changes relating to lipid metabolism may contribute towards the endothelial lesions observed in preeclampsia. Thus, the aim of the present study was to evaluate the lipid profile among patients who present preeclampsia and correlate these parameters with 24-hour proteinuria. DESIGN AND SETTING: Cross-sectional analytical study including 77 pregnant patients seen at Hospital Dório Silva. METHODS: This study involved 42 women with preeclampsia and 35 healthy pregnant women in the third trimester of pregnancy as controls. Blood samples were obtained from all the patients, and the serum levels of triglycerides, total cholesterol, low-density lipoproteins (LDL), high-density lipoproteins (HDL) and very low density lipoproteins (VLDL) were determined. Cases and controls were matched for maternal age, gestational week and body mass index. RESULTS: The VLDL and triglyceride values from the women with preeclampsia were significantly higher than those of the healthy women. There was a positive correlation between increased proteinuria and higher VLDL and triglyceride levels in patients with preeclampsia. CONCLUSION: Among the patients with preeclampsia, higher VLDL and triglyceride levels were positively correlated with proteinuria. These observations indicate that the pregnant women who presented elevated lipid levels were more susceptible to cardiovascular disorders and, consequently, pre-eclampsia.

CONTEXTO E OBJETIVO: A pré-eclâmpsia é um distúrbio que ocorre apenas durante a gravidez e as alterações pós-parto relacionadas ao metabolismo lipídico podem contribuir para a lesão endotelial observada nessa afecção. Assim, o objetivo do presente estudo foi avaliar o perfil lipídico em pacientes que apresentaram pré-eclâmpsia e correlacionar estes parâmetros com a proteinúria de 24 horas. TIPO DE ESTUDO E LOCAL: Estudo transversal analítico, incluindo 77 pacientes grávidas atendidas no Hospital Dório Silva. MÉTODOS: Este estudo envolveu 42 mulheres com pré-eclâmpsia e 35 gestantes saudáveis no terceiro trimestre de gravidez como controle. Amostras de sangue foram obtidas de todas as pacientes e os níveis séricos de triglicérides, colesterol total, lipoproteínas de baixa densidade (LDL), lipoproteínas de alta densidade (HDL) e lipoproteínas de muito baixa densidade (VLDL) foram determinados. Casos e controles foram pareados por idade materna, semana gestacional e índice de massa corporal. RESULTADOS: Os valores de VLDL e triglicérides, obtidos de mulheres com pré-eclâmpsia foram significativamente maiores quando comparados com mulheres saudáveis. Houve uma correlação positiva entre o aumento da proteinúria e concentrações elevadas de VLDL e triglicérides, em pacientes com pré-eclâmpsia. CONCLUSÃO: Nas pacientes com pré-eclâmpsia foram observadas as maiores concentrações de VLDL e os níveis de triglicérides estão correlacionados positivamente com proteinúria. Estas observações indicam que as mulheres grávidas que apresentam níveis elevados de lipídios, são mais suscetíveis a doenças cardiovasculares e, consequentemente, a pré-eclâmpsia.

VEGF en capa muscular de vasos placentarios: expresión en preeclampsia y asociación con status antioxidante / VEGF in muscular layer of placental vessels: expression in preeclampsia and its association with the antioxidant status

Introducción: La preeclampsia es una enfermedad gestacional de origen placentario, de alta prevalencia y morbi-mortalidad materna y fetal. Su patogenia es desconocida, aunque sabemos que en ella ocurre placentación anómala e isquemia placentaria, que conlleva desarrollo de estrés oxidativo (EO) y disfunción endotelial. En condiciones normales la perfusión placentaria es regulada fundamentalmente por óxido nítrico (NO). El factor de crecimiento vascular endotelial (VEGF) es clave en su modulación, aumentando la actividad de enzimas productoras de NO, manteniendo una perfusión placentaria y gestación normales. Objetivo: Caracterizar el perfil de parámetros oxidativos en preeclampsia, asociado con expresión de VEGF en capa muscular de vasos placentarios (CMVP). Metodología: Estudio analítico, observacional, transversal. Se tomaron muestras placentarias y plasmáticas de embarazadas con preeclampsia (n=12) y embarazos normales (n=15). En placenta se determinó: expresión de VEGF en CMVP, malondialdehído y actividad enzimática antioxidante–superóxido dismutasa, glutatión peroxidasa y catalasa. En plasma materno se determinó: F2-isoprostanos y capacidad plasmática antioxidante total (FRAP). Resultados: Pacientes con preeclampsia mostraron mayor expresión de VEGF en CMVP y reducción del FRAP, incremento de F2-isoprostanos y malondialdehído, y menor actividad de superóxido dismutasa (p<0.05). Discusión: Expresión de VEGF en CMVPy parámetros de EO aumentan en preeclampsia. En condiciones normoxémicas, VEGF en CMVP estimula la producción de NO, manteniendo una perfusión placentaria y gestación normales. En condiciones de hipoxia, EO y bajas defensas antioxidantes, como la preeclampsia, VEGF en CMVP favorecería la producción de pro-oxidantes en desmedro de la de NO, lo que contribuiría a explicar la fisiopatología de esta enfermedad.

Introduction: Preeclampsia is a systemic pregnancy disorder, which has high prevalence and high maternal and fetal mortality associated. Its pathogenesis is unknown, but is thought to occur in three phases: abnormal placentation, placental ischemia, which involves development of oxidative stress (OS), and endothelial dysfunction. During normal placental perfusion is regulated primarily by nitric oxide (NO). The vascular endothelial growth factor (VEGF) is a key modulator, increasing the activity of enzymes producing NO, maintaining placental perfusion and normal pregnancy. Objective: To characterize the profile of oxidative parameters in Preeclampsia, associated with VEGF expression in muscular layer of placental vessels (MLPV).Methodology: Analytical, observational, transversal study. Placental and blood plasma samples were taken of pregnant women with preeclampsia (n=12) and normal pregnancies (n=15). In placenta was determined: expression of VEGF in MLPV, malondialdehyde and antioxidant enzyme activity - superoxide dismutase, glutathione peroxidase and catalase. Was determined in maternal plasma F2-isoprostanes and plasma total antioxidant capacity (FRAP). Results: Patients with preeclampsia showed higher expression of VEGF in MLPV and reduced FRAP, increased F2-isoprostanes and malondialdehyde, and decreased activity of superoxide dismutase (p <0.05). Discussion: VEGF expression in MLPV and parameters of OS are both increased in preeclampsia. In normal, VEGF in MLPV stimulates NO production, maintaining a normal pregnancy and placental perfusion. Under hypoxic conditions, OS and low antioxidant defenses, as in preeclampsia, VEGF in MLPV favors the production of pro oxidant agents, at the expense of NO, which would help explain the pathophysiology of this disease.

Concentraciones de interleucina-2 en pacientes con preeclampsia a término y pretérmino / Interleukin 2 concentrations in preterm and term preeclamptic patients

Antecedentes: Existen resultados contradictorios sobre las concentraciones de interleucina-2 (IL-2) en pre-eclámpticas y se desconoce si existen diferencias en las concentraciones al momento del diagnóstico. Objetivo: Comparar las concentraciones de IL-2 en pacientes preecláticas de término y de pretérmino. Método: Se seleccionaron 50 pacientes: 20 preeclámpticas de pretérmino (grupo A) y 30 de término (grupo B). Las muestras de sangre para la determinación de IL-2 se recolectaron antes del parto e inmediatamente después del diagnóstico de preeclampsia. Resultados: No hubo diferencias signifcativas con relación a edad materna, índice de masa corporal, valores promedio de presión arterial sistólica y diastólica al momento de la toma de la muestra. Las concentraciones de IL-2 fueron similares en el grupo de preeclámpticas pretérmino (67,5 +/- 31,8 pg/ml) y el grupo de preeclámpticas de término (69,6 +/- 28,5 pg/ml). No hubo correlación signifcativa entre las concentraciones de IL-2 con los valores promedio de presión arterial sistólica y diastólica. Conclusiones: Las pacientes preeclámpticas con embarazos pretérmino presentaron concentraciones similares de interleucina-2 al compararlo con preeclampticas a término al momento del diagnóstico. Los hallazgos de la investigación sugerirían una falta de activación de los linfocitos T en preeclámpticas.

Background: There are contradictory results about interleukin-2 (IL-2) concentrations in preeclamptic patients and is unknown if there are differences in concentrations at the time of diagnosis. Objective: To compare concentrations of IL-2 in term and preterm preeclamptic patients. Method: Fifty patients were selected. Twenty preterm preeclamptic patients (group A) and thirty term preeclamptic patients (group B) were selected. Blood samples for IL-2 were collected in all patients before labor and immediately after diagnosis of preeclampsia. Results: There were not signifcant differences related to a maternal age, body mass index and mean values of systolic and diastolic blood pressure at the moment of collecting samples. There were signifcant differences between groups in gestational age. There also was not signifcant difference in IL-2 concentrations in the study group (67.5 +/- 31.8 pg/ml) and patients in control group (69.6 +/- 28.5 pg/ml). There was not signifcant correlation between interlukin-2 and mean values of systolic and diastolic blood pressure. Conclusion: Preeclamptic patients with preterm pregnancies presented similar interleukin-2 concentrations when compared to term preeclamptic patients at the time of diagnosis. The fnding of this research suggests a lack of activation of T-lymphocytes in preeclamptic patients.

Preeclampsia, migración celular y canales iónicos / Preeclampsia, cellular migration and ion channels

En la placenta humana, el sinciciotrofoblasto es la barrera que regula el transporte de nutrientes, solutos y agua entre la sangre materna y fetal. Dentro de este movimiento transepitelial se encuentra el del Na+, su contribución a la presión osmótica es fundamental en la regulación del volumen de líquido extracelular. El canal epitelial de sodio sensible al amiloride (ENaC) media el transporte de Na+ desde el lumen hacia el interior celular en numerosos epitelios absortivos. Está regulado por la aldosterona, vasopresina, catecolaminas, estrógenos y progesterona. Es bloqueado por el amiloride y sus análogos. Para su activación, diversas proteasas lo escinden en la membrana plasmática y esto a su vez es regulado por la aldosterona. El ENaC está expresado también en la placenta humana y aunque su función no es conocida, podría participar en la homeostasis de agua y electrolitos. El ENaC también es influenciado por el estado de las proteínas del citoesqueleto y los cambios en el volumen celular alteran a su vez a éste. De esta manera existe una relación entre el ENaC y el citoesqueleto. Además, las corrientes de Na+ por el ENaC y otros canales de sodio participan en la migración celular en células normales y cancerosas. Aquí presentamos evidencias que avalan la hipótesis que el ENaC es necesario para la migración celular en células BeWo, derivadas del trofoblasto humano, que sintetizan hormonas y expresan el ENaC. Las células BeWO han sido utilizadas como modelo experimental para estudiar el transporte en células de placenta.

The syncytiotrophoblast acts in human placenta as a transporting barrier regulating the transference of nutrients, solutes and water between maternal and fetal blood. This transepithelial transport involves movement of Na+ and its contribution to the osmotic pressure is an important determinant of the extracellular fluid volume. ENaC is a channel that mediates entry of Na+ from the luminal fluid into the cells in many reabsorbing epithelia; it is aldosterone, vasopressin, insulin and catecholamine-inducible, modulated by estrogens and progesterone and blocked by amiloride and its analogs. Multiple proteases are involved in the proteolytic processing and activation of ENaC subunits and aldosterone alters the protease-protease inhibitors balance. ENaC is also expressed in human placenta; although its function is not well known, the Na+ conductive properties may participate in electrolyte and extracellular volume homeostasis. The activity of ENaC channels and other ion channels and transporters is regulated by the state of actin filaments; on the other hand, changes in volume influence the actin cytoskeleton. Thus, there is an interaction between ENaC and components of the apical membrane cytoskeleton. In addition to their role in cellular homeostasis and electrical properties, Na+ currents through ENaC and other sodium channels are involved in cell migration, well documented in normal and cancer cells. In this work we presented evidences supporting the hypothesis that ENaC channels are required for the migration of BeWo cells, a human hormone-synthesizing trophoblastic cell line that express the three subunits of the ENaC channels. BeWo cell line has also been used as a model to investigate the placental transport mechanisms.

Acciones de endotelina 1 y angiotensina II en embarazos complicados con preeclampsia / Endothelin 1 and angiotensin II in preeeclampsia

Introduction. It is generally thought that development of hypertension in preeclampsia (PE) is due to generalized endothelial dysfunction and/or results from an imbalance in the production and/or action of vasoactive factors, resulting in higher citosolic Ca2+ concentration which in turn leads to vasoconstriction and decreased blood pressure perfusion in organs, including the fetoplacental unit. Among vasoactive factors involved in blood pressure regulation, endothelin 1 (ET-1) and angiotensin II (Ang II) regulate citosolic Ca2+ concentrations and therefore are considered in this review. PE is associated with higher circulating and placental ET-1 levels, observation that explains, at least in part, vasoconstriction and oxidative stress. Higher and lower Ang II sensitivity seen in PE and normal pregnancy, respectively, could not be explained by changes in renin-angiotensin system components, including Ang II receptors (ATI). During normal pregnancy, ATI receptors are found as monomers and are inactivated by reactive oxygen species (ROS) leading to lower Ang II sensitivity. In contrast, PE is associated with increased ATl/bradicinin receptors (B2) heterodimers which are resistant to inactivation by ROS, maintaining increased ATI-receptor stimulated signaling in PE. In adittion, AT-1 agonistic antibodies (AT1-AA) obtained from PE women increases intracellular Ca2+, NADPH oxidase components and ROS, effects not observed with normal pregnancy AT1-AA. Conclusion. High ET-1 levels, the presence of AT1/B2 receptor heterodimers and increased AT1-AA are involved, at least in part, in the hypertensive and oxidative stress states in PE.

Introducción. Se reconoce que el desarrollo de la hipertensión en la preeclampsia (PE) resulta del daño endotelial generalizado y/o de la falta de equilibrio en la producción y/o acción de agentes vasoactivos, lo que conlleva al incremento en la concentración citosólica de Ca2+ que resulta en vasoconstricción y disminución de la perfusión sanguínea en los órganos, incluyendo la unidad fetoplacentaria. Dentro de los factores vaso-activos que regulan la presión arterial, en la presente revisión se consideró a la endotelina 1 (ET-1) y a la angiotensina II (Ang II), factores que regulan la concentración citosólica de Ca2+. En comparación con el embarazo normal, la PE se asocia con mayor concentración en suero y placenta de ET-1, lo que explica en parte la vasoconstricción y el estado de estrés oxidativo. La respuesta exagerada en la PE y el estado de refractariedad en el embarazo normal a la Ang II no pueden explicarse por componentes del sistema renina-angiotensina, incluyendo a los receptores de Ang II (ATI). Durante el embarazo normal los receptores AT-1 se encuentran en forma de monómeros y son inactivados por las especies reactivas de oxígeno (ROS), lo que se asocia con menor respuesta a Ang II. En cambio, la respuesta exagerada a la Ang II durante la PE puede deberse a la heterodimerizacion de los receptores ATI con los de bradicinina (B2), estado que les confiere resistencia a la inactivación por las especies reactivas de oxígeno (ROS), lo que explica el incremento en la concentración del Ca2+ intracelular. Además, los anticuerpos agonistas del receptor ATI (AT1-AA) de mujeres PE aumenta la concentración de Ca2+ intracelular, de la NADPH oxidasa y de ROS, efectos que no se presentan al utilizar AT1-AA de embarazadas normotensas. Conclusión. Las altas concentraciones de ET-1, la presencia de receptores ATI en forma de heterodimeros ATI/ B2 y el aumento en los AT1-AA explican en parte, el estado de hipertensión y de estrés oxidativo de la PE.

Hierro, oxígeno y desarrollo placentario en la génesis de la preeclampsia: Efectos de la altura en Ecuador / Iron, oxygen and placental development in the etiology of preeclampsia: Effects of high altitude in Ecuador

Preeclampsia is the second cause of maternal death in Ecuador. The etiology of this condition is probably a placental alteration, although the details are not well known. The development of the placenta is closely related to the availability of oxygen. A defect in the differentiation of trophoblastic cells due to a faulty sensitization to changes in oxygen pressure, could be the cause of the alteration in placental development. The role of iron and local environmental conditions of a susceptible population, should be considered in the study of the etiology of preeclampsia. In the Andrean area of Ecuador, the high incidence of preeclampsia could be explained by the high prevalence of anemia and high altitude. However more studies are required to establish a close link between the environmental conditions of this area and the imperfect placental development.

Analysis of placental growth factor in placentas of normal pregnant women and women with hypertensive disorders of pregnancy / 华中科技大学学报（医学）（英德文版）

To investigate the expressions of placental growth factor (PLGF) in placenta with hypertensive disorders of pregnancy (HDP), 45 women with HDP and 20 normally pregnant women were studied. Among 45 women with HDP, there were 23 cases of severe preeclampsia and one case of eclampsia. The location and level of PLGF proteins was determined by immunohistochemistry and Western blot. The expression of PLGF mRNA in placenta was assessed by reverse transcriptional-polymerase chain reaction (RT-PCR). The results showed that: (1) The distribution of PLGF in placenta with HDP was similar to normal one, which was mainly in the cytoplasm of villous syncytiotrophoblast and villous stroma; (2) The expression of PLGF protein was significantly decreased in placentas with mild and severe preeclampsia compared to the normal ones (0.3 +/- 0.4 vs 0.6 +/- 0.4, 0.2 +/- 0.5 vs 0.6 +/- 0.4, P 0.05); (3) The transcription levels of the PLGF mRNA in placentas with preeclampsia were significantly lower than in normal groups (3.33 +/- 0.39 vs 4.87 +/- 0.60, 1.97 +/- 0.29 vs 4.87 +/- 0.60, P < 0.01), and no differences were found between the gestational hypertension placenta and normal groups. These findings suggest that the abnormal expression of PLGF in placentas is related to the pathogenesis of HDP.