Determinação de adenosina deaminase, fator de necrose tumoral-alfa e interleucina-1 em gestantes portadoras de pré-eclâmpsia

Preeclampsia is a specific disorder of pregnancy, characterized by arterial hypertension and proteinuria detected after 20 weeks of gestation. This pathology is associated with hyperuricemia, higher levels of pro-inflammatory cytokines, enhanced leukocyte activation and oxidative stress. Adenosine deaminase (ADA) is an enzyme present in all human tissues and, it is involved with the maturation of the immune system. Although its function is not fully understood, ADA is considered an indicator of cellular inflammation and, its increased serum concentration is observed in inflammatory diseases, such as tuberculosis and rheumatoid arthritis. This study aimed to assess serum ADA levels in preeclamptic patients (PE) compared with normotensive pregnant (NT) and non-pregnant women (NP), and to correlate these values with TNF-α and IL-1β production. Ninety pregnant women were included: 60 were pre-eclamptic and 30 were normotensive matched for gestational age. As control group 20 healthy non-pregnant women matched with pregnant for age were included. Peripheral blood mononuclear cells (PMMC) obtained from the three groups studied were cultured with or without lipopolysaccharide (LPS) for 18h at 37oC, and TNF-α and IL-1β production was assessed in the supernatant of cultures by enzyme immunoassay (ELISA). ADA plasmatic concentration was determined by colorimetric method. The results show that ADA plasma levels were significantly higher in PE group compared with NT and NP groups. A positive correlation between ADA and uric acid levels was detected in preeclamptic women. There was no significant difference in relation to ADA levels when PE patients were classified in early and late-onset PE. The endogenous production of IL-1β and TNF-α by PBMC was significantly higher in PE group than in NT and NP women, showing the activation state of these cells in PE. LPS induced...(Complete abstract click electronic access below)

Efeito da silibinina sobre o fator de transcrição nuclear-kB e produção de citocinas inflamatórias por células mononucleares de gestantes portadoras de pré-eclâmpsia

Pre-eclampsia (PE) is a complication of human pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. Its incidence varies from 5% to 7% of pregnancies and is a major cause of morbidity and maternal and fetal mortality. This is a multisystemic disease, with focus on vascular dysfunction and is closely related to the exacerbated activation of the immune system. In addition to increased activation of monocytes and granulocytes, there is an elevated production of proinflammatory cytokines in pregnant women with PE. The nuclear transcription factor-kB (NF-kB) is present in the cells of the immune system and is responsible for transcription of genes related to inflammation. Whereas the PE is associated with intense inflammatory response, the use of substances modulating the activity of NF-kB factor could be useful in alleviating the inflammation present in these patients. Silibinin is the main component of silymarin, a polyphenolic extract obtained from fruits and seeds of Sylibum marianum with potent hepatoprotective, anti-inflammatory and anti-fibrotic activities. The silibinin mechanism of action includes the ability to inhibit NF-kB activation and, consequently, its migration to the nucleus. The objective of this study was to assess whether silibinin modulates the activity of NF-kB and the production of inflammatory cytokines in mononuclear cells of patients with PE. We evaluated 34 pregnant women with PE, 20 normotensive pregnant women (GN) and 15 non-pregnant women (NG). Peripheral blood mononuclear cells (PBMC) were obtained from those groups of women and cultured in the presence or absence of silibinin (5 uM or 50 uM) and stimulated or not with lipopolysaccharide (LPS) for 18 h to obtain supernatant for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1β) by enzyme immunoassay (ELISA). The cells were...(Complete abstract click electronic access below)

Associação entre expressão de receptores TLR2 e TLR4 e produção de TNF-alpha e IL-10 por monócitos de gestantes portadoras de pré-eclâmpsia

Preeclampsia (PE) is a pregnancy specific syndrome characterized by a systemic inflammatory response, with higher intensity than that observed in normal pregnancy. Cells of the immune system, such as monocytes and granulocytes are endogenously activated and secrete high levels of free radicals and inflammatory cytokines. The objective of this study was to assess the activation state of monocytes from pregnant women with preeclampsia by endogenous expression of TLR2 e TLR4 receptors and to correlate the expression of TLR2 and TLR4 on monocytes surface of pregnant women with PE with the production of tumor necrosis factor-alpha (TNF- and interleukin-10 (IL-10) by these cells stimulated or not with peptidoglycan (PG) and lipopolysaccharide (LPS), as agonists agents of TLR2 and TLR4, respectively. We evaluated 15 pregnant women with PE, 15 normotensive pregnant women (NT) and 15 non-pregnant (NP). Peripheral blood monocytes were incubates in the presence or absence of LPS or PG. The supernatant obtained after 18h of culture was aspirated and used for TNF- and IL-10 determination by enzyme immunoassay (ELISA). The endogenous expression of TLR2 and TLR4 receptors was evaluated by flow cytometry. Our results showed significant highly concentrations of TNF- and TLR4 expression in monocytes of preeclamptic women when compared with NT and NP. Normal pregnant women presented higher levels of IL-10 in comparison with PE and NP groups. TLR2 expression was similar in the three groups studied. Therefore, our study highlights the important role of TLR4 in PE and the consequent high production of TNF- by monocytes of these patients, as well as the potential mechanism involving low levels of IL-10 in the pathophysiology of the disease. These observations demonstrate the strong link between the pathology of PE and the immune system of these patients

Determinação de fatores angiogênicos e anti-angiogênicos em plasma de gestantes portadoras de pré-eclâmpsia precoce e tardia

Changes in circulating angiogenic factors have been implicated in the pathogenesis of preeclampsia. Thus, evaluation of angiogenesis agonist and antagonist factors is of greater importance to understand the mechanisms responsible for this disorder. The objective of the present study was to evaluate whether circulating angiogenic and anti-angiogenic factors may differentiate early-onset from late-onset preeclampsia. The study was conducted in 86 women with preeclampsia diagnosed in the third trimester of pregnancy. Preeclampsia was classified according to the onset of clinical manifestation in early-onset (before 34 weeks of gestation; n=31) or in late-onset (from 34 weeks of gestation on; n=55) preeclampsia. Serum was obtained from the patients in the moment of the diagnosis and assayed for placental growth factor (PlGF), vascular endothelial growth factor (VEGF), soluble Endoglin (sEng) and soluble form of vascular endothelial growth factor receptor (sVEGFR-1) determination by enzyme-linked immunosorbent assay. The results showed that early-onset preeclampsia was characterized by significant lower levels of PlGF (median 38.3 vs 123.5 pg/mL) and VEGF (median 23.1 vs 35.3 pg/mL) in serum as well as by higher serum levels of sEng (median 54.7 vs 42.1 pg/mL) and sVEGFR-1 (median 5211.0 vs 4657.6 pg/mL) compared with late-onset preeclampsia. In this study serum levels of angiogenic and anti-angiogenic factors prove useful in differentiating early-onset from late-onset preeclampsia in the third trimester of pregnancy. Therefore, these findings suggest that angiogenic factors determination may indicate that early- and late-onset preeclampsia have different pathophysiology

Eficácia da haptoglobina como marcador de hemólise no diagnóstico da síndrome HELLP

Introduction: The HELLP syndrome is a severe complication of pregnant women with preeclampsia (PE), characterized by association of hemolysis, changes in liver enzymes and thrombocytopenia. Hemolysis, defined by the presence of microangiopathic hemolytic anemia, is one of the characteristics in this syndrome. However, as hemolysis occurs in a short time there is some difficulty in its laboratory diagnosis. Therefore, the search for a more sensitive and specific method for hemolysis determination may help in the early diagnosis of the HELLP syndrome. Objectives: a) To determine the plasma concentration of haptoglobin in normotensive pregnant women and in pregnant women with PE, classified into mild PE, severe PE and HELLP/partial HELLP syndrome; b) To compare the efficacy of haptoglobin plasma concentration and serum total bilirubin as criteria for hemolysis diagnosis in HELLP/partial HELLP syndrome. Methods: We conducted a cross-sectional analytical and comparative study involving 66 pregnant women diagnosed with PE, being 25 cases with mild PE, 28 with severe PE, and 13 with HELLP/partial HELLP syndrome. Twenty-one normotensive pregnant women were included for comparison of haptoglobin plasma concentration between the groups and to determine the normal values for pregnant women. The variables studied were: maternal age, gestational age, systolic and diastolic blood pressure, proteinuria, hematocrit and hemoglobin values, platelet count, serum total bilirubin, lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (AST) and glutamic-pyruvic transaminase (ALT), urea, creatinine and uric acid, and also plasma concentrations of haptoglobin. The results were analyzed by nonparametric tests, with a significance level of 5%. Results: The values of urea, uric acid, AST, ALT and LDH were significantly higher, while the number of platelets was lower in pregnant women with HELLP/partial HELLP syndrome compared to pregnant women with mild PE and ...

Características clínicas e laboratoriais de gestantes com pré-eclâmpsia versus hipertensão gestacional

Purpose: To compare clinical and laboratory characteristics, obstetric and perinatal outcomes of patients with pre-eclampsia versus gestational hypertension. Methods: A retrospective study was carried out to analyze medical records of patients diagnosed with pre-eclampsia and gestational hypertension whose pregnancies were resolved within a period of 5 years, for a total of 419 cases. We collected clinical and laboratory data, obstetric and perinatal outcomes. Comparisons between groups were performed using the test suitable for the variable analyzed: unpaired t test, Mann-Whitney U test or χ2test, with the level of significance set at p<0.05. Results: Were evaluated 199 patients in the gestational hypertension group (GH) and 220 patients in the pre-eclampsia group (PE). Mean body mass index was 34.6 kg/m2 in the GH group and 32.7 kg/m2 in the PE group, with a significant difference between groups. The PE group showed higher systolic and diastolic blood pressure and higher rates of abnormal values in the laboratory tests, although the mean values were within the normal range. Cesarean section was performed in 59.1% of cases of PE and in 47.5% of the GH group; and perinatal outcomes in terms of gestational age and birth weight were significantly lower in the PE group. Conclusion: Women with gestational hypertension exhibit epidemiological characteristics of patients at risk for chronic diseases. Patients with pre-eclampsia present clinical and laboratory parameters of greater severity, higher rates of cesarean delivery and worse maternal and perinatal outcomes.

Clinical and laboratory characteristics of pregnant women with preeclampsia versus gestational hypertension

To compare clinical and laboratory characteristics, obstetric and perinatal outcomes of patients with pre-eclampsia versus gestational hypertension. A retrospective study was carried out to analyze medical records of patients diagnosed with pre-eclampsia and gestational hypertension whose pregnancies were resolved within a period of 5 years, for a total of 419 cases. We collected clinical and laboratory data, obstetric and perinatal outcomes. Comparisons between groups were performed using the test suitable for the variable analyzed: unpaired t test, Mann-Whitney U test or χ2 test, with the level of significance set at p<0.05. Were evaluated 199 patients in the gestational hypertension group (GH) and 220 patients in the pre-eclampsia group (PE). Mean body mass index was 34.6 kg/m2 in the GH group and 32.7 kg/m2 in the PE group, with a significant difference between groups. The PE group showed higher systolic and diastolic blood pressure and higher rates of abnormal values in the laboratory tests, although the mean values were within the normal range. Cesarean section was performed in 59.1% of cases of PE and in 47.5% of the GH group; and perinatal outcomes in terms of gestational age and birth weight were significantly lower in the PE group. Women with gestational hypertension exhibit epidemiological characteristics of patients at risk for chronic diseases. Patients with pre-eclampsia present clinical and laboratory parameters of greater severity, higher rates of cesarean delivery and worse maternal and perinatal outcomes.

Associação entre ácido úrico materno com resultados maternos e perinatais na pré-eclâmpsia

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Effects of Matrix Metalloproteinase (MMP)-2 Polymorphisms on Responsiveness to Antihypertensive Therapy of Women with Hypertensive Disorders of Pregnancy

Imbalanced matrix metalloproteinase (MMP) expression, including MMP-2, has been demonstrated in pre-eclampsia. However, little is known about the effect of polymorphisms in MMP-2 gene on hypertensive disorders of pregnancy. We examined whether two functional MMP-2 polymorphisms (g.-1306C>T and g.-735C>T) are associated with pre-eclampsia and/or gestational hypertension and whether these polymorphisms affect therapeutic responses in women with these conditions. We studied 216 healthy pregnant women (HP), 185 patients with gestational hypertension (GH) and 216 patients with pre-eclampsia (PE). They were stratified as responsive or non-responsive to antihypertensive therapy according to clinical and laboratorial parameters of therapeutic responsiveness. Genomic DNA was extracted from whole blood and genotypes for g-1306C>T and g.-735C>T polymorphisms were determined by real-time PCR using Taqman allele discrimination assays. Haplotype frequencies were inferred using the PHASE 2.1 program. The distributions of MMP-2 genotypes and haplotypes were similar in HP, GH and PE patients (p > 0.05). In addition, we found no significant differences in MMP-2 genotype or haplotype frequencies when GH or PE patients were classified as responsive or non-responsive to antihypertensive therapy (p > 0.05). Our results suggest that MMP-2 polymorphisms do not affect the susceptibility to hypertensive disorders of pregnancy. In parallel, MMP-2 polymorphisms apparently do not affect the responsiveness to antihypertensive therapy of women with these hypertensive disorders of pregnancy.

Maternal iNOS genetic polymorphisms and hypertensive disorders of pregnancy

Increased expression and activity of inducible nitric oxide synthase (iNOS) may contribute to the pathogenesis of pre-eclampsia (PE) and gestational hypertension (GH). However, no previous study has examined whether genetic polymorphisms in the iNOS gene are associated with PE or GH. We examined whether two functional, clinically relevant iNOS genetic polymorphisms (the C(-1026)A polymorphism, rs2779249, in the promoter region, and the G2087A polymorphism, rs2297518, in exon 16) are associated with GH or with PE. We studied 565 pregnant women: 212 healthy pregnant (HP), 166 pregnant with GH and 187 pregnant with PE. Genotypes were determined by real-time PCR, using the Taqman allele discrimination assay. The PHASE 2.1 program was used to estimate haplotype distributions in the three study groups. We found no significant association between the C(-1026)A polymorphism and PE or GH (P>0.05). However, we found the GA genotype and the A allele for the G2087A polymorphism at higher frequency in PE, but not in GH, compared with HP (P<0.05). The haplotype analysis showed no significant intergroup differences (P>0.05). These findings suggest that iNOS genetic variants may affect the susceptibility to PE, but not to GH. Journal of Human Hypertension (2012) 26, 547-552; doi:10.1038/jhh.2011.65; published online 30 June 2011

High aldosterone-to-renin variants of CYP11B2 and pregnancy outcome

BACKGROUND: Increased aldosterone concentrations and volume expansion of normal pregnancies are hallmarks of normal pregnancies and blunted in pre-eclampsia. Accordingly, we hypothesized an active mineralocorticoid system to protect from pre-eclampsia. METHODS: In pregnant women (normotensive n = 44; pre-eclamptic n = 48), blood pressure, urinary tetrahydro-aldosterone excretion and activating polymorphisms (SF-1 site and intron 2) of the aldosterone synthase gene (CYP11B2) were determined; 185 non-pregnant normotensive individuals served as control. Amino acid-changing polymorphisms of the DNA- and agonist-binding regions of the mineralocorticoid receptor were evaluated by RT-PCR, SSCP and sequencing. RESULTS: Urinary tetrahydro-aldosterone excretion was reduced in pre-eclampsia as compared to normal pregnancy (P < 0.05). It inversely correlated with blood pressure (r = 0.99, P < 0.04). Homozygosity for activating CYP11B2 polymorphisms was preferably present in normotensive as compared to pre-eclamptic pregnancies, identified (intron 2, P = 0.005; SF-1 site, P = 0.016). Two mutant haplotypes decreased the risk of developing pre-eclampsia (RR 0.16; CI 0.05-0.54; P < 0.001). In contrast, intron 2 wild type predisposed to pre-eclampsia (P < 0.0015). No functional mineralocorticoid receptor mutant has been observed. CONCLUSIONS: High aldosterone availability is associated with lower maternal blood pressure. In line with this observation, gain-of-function variants of the CYP11B2 reduce the risk of developing pre-eclampsia. Mutants of the mineralocorticoid receptor cannot explain the frequent syndrome of pre-eclampsia.

Angiotensin receptor agonistic autoantibody is highly prevalent in preeclampsia: correlation with disease severity.

Preeclampsia (PE), a syndrome affecting 5% of pregnancies, characterized by hypertension and proteinuria, is a leading cause of maternal and fetal morbidity and mortality. The condition is often accompanied by the presence of a circulating maternal autoantibody, the angiotensin II type I receptor agonistic autoantibody (AT(1)-AA). However, the prevalence of AT(1)-AA in PE remains unknown, and the correlation of AT(1)-AA titers with the severity of the disease remains undetermined. We used a sensitive and high-throughput luciferase bioassay to detect AT(1)-AA levels in the serum of 30 normal, 37 preeclamptic (10 mild and 27 severe), and 23 gestational hypertensive individuals. Here we report that AT(1)-AA is highly prevalent in PE ( approximately 95%). Next, by comparing the levels of AT(1)-AA among women with mild and severe PE, we found that the titer of AT(1)-AA is proportional to the severity of the disease. Intriguingly, among severe preeclamptic patients, we discovered that the titer of AT(1)-AA is significantly correlated with the clinical features of PE: systolic blood pressure (r=0.56), proteinuria (r=0.70), and soluble fms-like tyrosine kinase-1 level (r=0.71), respectively. Notably, only AT(1)-AA, and not soluble fms-like tyrosine kinase-1, levels are elevated in gestational hypertensive patients. These data serve as compelling clinical evidence that AT(1)-AA is highly prevalent in PE, and its titer is strongly correlated to the severity of the disease.

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy.

TNF-α (tumor necrosis factor-α) is a potent pro-inflammatory cytokine that regulates the permeability of blood and lymphatic vessels. The plasma concentration of TNF-α is elevated (> 1 pg/mL) in several pathologies, including rheumatoid arthritis, atherosclerosis, cancer, pre-eclampsia; in obese individuals; and in trauma patients. To test whether circulating TNF-α could induce similar alterations in different districts along the vascular system, three endothelial cell lines, namely HUVEC, HPMEC, and HCAEC, were characterized in terms of 1) mechanical properties, employing atomic force microscopy; 2) cytoskeletal organization, through fluorescence microscopy; and 3) membrane overexpression of adhesion molecules, employing ELISA and immunostaining. Upon stimulation with TNF-α (10 ng/mL for 20 h), for all three endothelial cells, the mechanical stiffness increased by about 50% with a mean apparent elastic modulus of E ~5 ± 0.5 kPa (~3.3 ± 0.35 kPa for the control cells); the density of F-actin filaments increased in the apical and median planes; and the ICAM-1 receptors were overexpressed compared with controls. Collectively, these results demonstrate that sufficiently high levels of circulating TNF-α have similar effects on different endothelial districts, and provide additional information for unraveling the possible correlations between circulating pro-inflammatory cytokines and systemic vascular dysfunction.

The detrimental role of angiotensin receptor agonistic autoantibodies in intrauterine growth restriction seen in preeclampsia.

Growth-restricted fetuses are at risk for a variety of lifelong medical conditions. Preeclampsia, a life-threatening hypertensive disorder of pregnancy, is associated with fetuses who suffer from intrauterine growth restriction (IUGR). Recently, emerging evidence indicates that preeclamptic women harbor AT(1) receptor agonistic autoantibodies (AT(1)-AAs) that contribute to the disease features. However, the exact role of AT(1)-AAs in IUGR and the underlying mechanisms have not been identified. We report that these autoantibodies are present in the cord blood of women with preeclampsia and retain the ability to activate AT(1) receptors. Using an autoantibody-induced animal model of preeclampsia, we show that AT(1)-AAs cross the mouse placenta, enter fetal circulation, and lead to small fetuses with organ growth retardation. AT(1)-AAs also induce apoptosis in the placentas of pregnant mice, human villous explants, and human trophoblast cells. Finally, autoantibody-induced IUGR and placental apoptosis are diminished by either losartan or an autoantibody-neutralizing peptide. Thus, these studies identify AT(1)-AA as a novel causative factor of preeclampsia-associated IUGR and offer two possible underlying mechanisms: a direct detrimental effect on fetal development by crossing the placenta and entering fetal circulation, and indirectly through AT(1)-AA-induced placental damage. Our findings highlight AT(1)-AAs as important therapeutic targets.

PLACENTAL URIC ACID TRANSPORTER GLUT9 IS MODULATED BY FREE IODINE

PLACENTAL URIC ACID TRANSPORTER GLUT9 IS MODULATED BY FREE IODINE Objectives: Materno-fetal transplacental transport is crucial for the fetal well-being. The altered expression of placental transport proteins under specific pathophysiological conditions may affect the intrauterine environment. Pre-eclampsia is often associated with high maternal uric acid serum levels. The regulation of the placental uric transport system and its transporter glucose transporter (GLUT)-9 are not fully understood yet. The aim of this study was to investigate the placental urate transport and to characterize its transporter GLUT9. Methods: In this study we used a transepithelial transport (Transwell®) model to assess uric acid transport activity. Electrophysiological techniques and radioactive ligand up-take assays were used to measure transport activity of GLUT9 expressed in Xenopus oocytes. Results: In the Transwell/model uric acid is transported across the BeWo choriocarcinoma cell monolayer with 530 pmol/min at the linear stage. We could successfully over-express GLUT9 using the Xenopus laevis oocytes expression system. Chloride modulates the urate transport system: interestingly replacing chloride with iodine resulted in a complete loss of urate transport activity.We determined the IC50 of iodine at 30uM concentration. In radioactive up-take experiments iodinehad noeffect on uric acid transport. Conclusions: In vitro the “materno-fetal” transport of uric acid is slow. This indicates that in vivo the child is protected from short-term fluctuations of maternal uric acid serum concentrations. The different results regarding iodine-mediated regulation of GLUT9 transport activity between electrophysiological and radioactive ligand uptake experiments may suggest that iodine does not directly inhibit uric acid transport, but changes the mode of up-take from an electrogenic to an electroneutral transport. GLUT9 is not an uric acid uniporter, there are more ions involved in the transport. This may allow regulating uric acid transport by the change from an active to a passive transport.