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Autophagy is a lysosomal degradation pathway that removes protein aggregates and damaged organelles maintaining cellular integrity. It seems to be essential for cell survival during stress, starvation, hypoxia, and consequently to the placenta implantation and development. Preeclampsia (PE) is a multisystemic disorder characterized by the onset of hypertension associated or not with proteinuria and other maternal complications. Considering that the placenta seems to play an important role in the pathogenesis of PE, the objective of the present study was to evaluate protein levels of light chain protein (LC3), beclin-1, and the mammalian target of rapamycin (mTOR) in the placenta of pregnant women with PE. Placental tissues collected from 20 women with PE and 20 normotensive (NT) pregnant women were evaluated for LC3, beclin-1, and mTOR expression by qPCR and immunohistochemistry. The mRNA for LC3 and beclin-1 were significantly lower, while mTOR gene expression was significantly higher in the placenta of pregnant women with PE than in the NT group. Placentas of PE women showed significantly decreased protein expression of LC3-II and beclin-1, whereas mTOR was significantly increased compared with the NT pregnant women. There was a negative correlation between protein expression of mTOR and LC3-II in the placental tissue of PE women. In conclusion, the results showed autophagy deficiency suggesting that failure in this degradation process may contribute to the pathogenesis of PE; however, new studies involving cross-talk between autophagy and inflammatory molecular mechanisms might help to better understand the autophagy process in this obstetric pathology.

Assuntos

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Autophagy is a lysosomal degradation pathway that removes protein aggregates and damaged organelles maintaining cellular integrity. It seems to be essential for cell survival during stress, starvation, hypoxia, and consequently to the placenta implantation and development. Preeclampsia (PE) is a multisystemic disorder characterized by the onset of hypertension associated or not with proteinuria and other maternal complications. Considering that the placenta seems to play an important role in the pathogenesis of PE, the objective of the present study was to evaluate protein levels of light chain protein (LC3), beclin-1, and the mammalian target of rapamycin (mTOR) in the placenta of pregnant women with PE. Placental tissues collected from 20 women with PE and 20 normotensive (NT) pregnant women were evaluated for LC3, beclin-1, and mTOR expression by qPCR and immunohistochemistry. The mRNA for LC3 and beclin-1 were significantly lower, while mTOR gene expression was significantly higher in the placenta of pregnant women with PE than in the NT group. Placentas of PE women showed significantly decreased protein expression of LC3-II and beclin-1, whereas mTOR was significantly increased compared with the NT pregnant women. There was a negative correlation between protein expression of mTOR and LC3-II in the placental tissue of PE women. In conclusion, the results showed autophagy deficiency suggesting that failure in this degradation process may contribute to the pathogenesis of PE; however, new studies involving cross-talk between autophagy and inflammatory molecular mechanisms might help to better understand the autophagy process in this obstetric pathology.

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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.

Assuntos

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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.

Assuntos

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OBJECTIVE: Pre-eclampsia (PE) is associated with maternal cardiac remodeling and diastolic dysfunction. The aim of this study was to assess and compare maternal left ventricular structure and diastolic function and levels of brain natriuretic peptide (BNP) in women with early-onset (< 34 weeks' gestation) vs those with late-onset (≥ 34 weeks' gestation) PE. METHODS: This was a prospective, cross-sectional, observational study of 30 women with early-onset PE, 32 with late-onset PE and 23 normotensive controls. Maternal cardiac structure and diastolic function were assessed by echocardiography and plasma levels of BNP were measured by enzyme immunoassay. RESULTS: Early- and late-onset PE were associated with increased left ventricular mass index and relative wall thickness compared with normotensive controls. In women with early-onset PE, the prevalence of concentric hypertrophy (40%) and diastolic dysfunction (23%) was also significantly higher (both P < 0.05) compared with women with late-onset PE (16% for both). Maternal serum BNP levels were significantly higher (P < 0.05) in women with early-onset PE and correlated with relative wall thickness and left ventricular mass index. CONCLUSIONS: Early-onset PE is associated with more severe cardiac impairment than is late-onset PE, as evidenced by an increased prevalence of concentric hypertrophy, diastolic dysfunction and higher levels of BNP. These findings suggest that early-onset PE causes greater myocardial damage, increasing the risk of both peripartum and postpartum cardiovascular morbidity. Although these cardiovascular effects are easily identified by echocardiographic parameters and measuring BNP, further studies are needed to assess their clinical utility. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Assuntos

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Silibinin is a polyphenolic plant flavonoid with anti-inflammatory properties. The present study investigated the effect of silibinin on oxidative metabolism and cytokine production - tumor necrosis factor-alpha (TNF-α), interleukin (IL)12, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6, IL-10, and transforming growth factor beta (TGF-ß1) - by peripheral blood monocytes (PBM) from preeclamptic pregnant women. It is a case-controlled study involving women with preeclampsia (PE, n = 30) compared with normotensive pregnant (NT, n = 30) and with non-pregnant (NP, n = 30) women. Monocytes were obtained and cultured with or without silibinin (5 µM or 50 µM) for 18 h. Superoxide anion (O2-) and hydrogen peroxide (H2O2) release were determined by specific assays, and cytokine levels were determined by immunoenzymatic assays (ELISA). Monocytes from preeclamptic women cultured without stimulus released higher levels of O22, H2O2 and TNF-α, and lower levels of IL-10 and TGF-ß1 than did monocytes from NT and NP women. Treatment in vitro with silibinin significantly inhibited spontaneous O2- and H2O2 release and TNF-α production by monocytes from preeclamptic women. The main effect of silibinin was obtained at 50 µM concentration. Thus, silibinin exerts anti-oxidative and anti-inflammatory effects on monocytes from preeclamptic pregnant women by inhibiting the in vitro endogenous release of reactive oxygen species and TNF-α production.

Assuntos

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INTRODUCTION: Pre-eclampsia (PE) is associated with profound changes in the maternal cardiovascular system. The new concept of early and late preeclampsia established the hypothesis that these two entities may be associated with different models of vascular adaptation. Studies of central hemodynamics are limited. The applanation tonometry is able to evaluate, noninvasively, several vascular features and can be used to study the pathophyology of different forms of preeclampsia. OBJECTIVES: To compare vascular parameters of pulse wave analysis in pregnant women with early and late preeclampsia, determined by applanation tonometry. METHODS: This was a cross-sectional study involving pregnant women with 34 early-onset PE (<34 weeks) and 51 late-onset (⩾34 weeks) PE. Central blood pressure, peripheral and central pulse pressure, augmentation index, the augmentation pressure, subendocardial viability ratio and the ejection duration were assessed noninvasively using applanation tonometry (SphygmoCor ®). Data were expressed as means±SD or as median and percentage. The mean was used for parameters with normal distribution and median for parameters that were not normally distribution. Comparisons between groups were performed using t-test, Mann-Whitney test or chi-square(c(2)) for numerical and categorical data, respectively. It was considered a significance level of 5%. Statistical analysis were done using SPSS 10.5. RESULTS: Compared to late-onset PE group, women that developed early-onset PE had higher augmentation index (24.2±13.1 vs 18.8±12.5; p=0.03). Any other paremeters presented significant differences between the groups. CONCLUSION: We found that early-onset PE is characterized by increased maternal arterial stiffness when compared late-onset PE, using applanation tonometry.

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INTRODUCTION: Hyperuricemia is a common finding in preeclamptic pregnancies and proteinuria, as well as hypertension are markers of preeclampsia. Production of anti-angiogenic proteins seems to be involved in the pathophysiology of hypertension and proteinuria in preeclampsia. OBJECTIVES: The purpose of this study was to evaluate whether there is an association between renal function and changes in serum levels of angiogenic factors in preeclamptic patients. METHODS: Serum was obtained from 83 preeclamptic patients in the last trimester of pregnancy for determination of uric acid. Placental growth factor (PlGF), vascular endothelial growth factor (VEGF) and soluble form of vascular endothelial growth factor receptor (sVEGFR-1) were evaluated in serum by an enzyme immunoassay. Proteinuria was determined in a 24-h urine collection. The concentration of angiogenic factors was compared with serum uric acid levels (<6mg/dL vs ⩾6mg/dL) and with proteinuria levels (<2g vs ⩾2g). Statistical analysis was performed using non-parametric tests with significance level set at 5%. RESULTS: In 40% of women with preeclampsia serum uric acid levels were ⩾6mg/dL, and proteinuria concentration ⩾2g was detected in 41% of patients. Positive correlation was observed between uric acid and proteinuria levels (r=0.7274; p<0.0001). Serum levels of PIGF were significantly lower in preeclamptic women with serum uric acid level ⩾6mg/dL compared with women with serum uric acid <6mg/dL (median 48.46 vs 117.32pg/mL). Significant difference between proteinuria ⩾2g and <2g was detected in relation to serum levels of PIGF (median 47.58 vs 114.24pg/mL), VEGF (median 25.35 vs 33.74pg/mL) and sVEGFR-1 (median 5386 vs 4605pg/mL). CONCLUSION: Elevation in circulating uric acid as well as proteinuria in preeclamptic women is associated with an altered angiogenic balance, suggesting that angiogenic factors may be involved in kidney dysfunction.

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INTRODUCTION: Preeclampsia is a human pregnancy-specific syndrome characterized by the onset of hypertension and proteinuria. These manifestations may occur before the 34th week of gestation or from this period on, being denominated early-onset or late-onset preeclampsia respectively. The etiology of both disorders seems to differ qualitatively; therefore, different strategies of prevention and treatment must be studied. OBJECTIVES: The aim of the present study is to determine whether the plasma levels of heat-shock proteins Hsp60 and Hsp70 as well as specific antibodies anti-Hsp60 and anti-Hsp70 may differentiate early-onset from late-onset preeclampsia. METHODS: We evaluated 175 pregnant women with PE (55 early-onset PE and 120 late-onset PE). Plasma was obtained from peripheral blood and Hsp60, Hsp70 as well as anti-Hsp60 and anti-Hsp70 antibody levels were determined by enzyme immunoassay. Uric acid levels were also determined in the plasma of patients. For statistical analyses, the Mann-Whitney U-test and the Spearman rank order correlation were applied with significance level set at 5%. RESULTS: Hsp70 levels obtained from early-onset PE group were significantly higher than the late-onset PE women and showed positive correlation with uric acid (r=0.4547; p=0.0028). The Hsp60 production was similar in both groups. Our results also indicate that there was no significant difference of anti-Hsp60 and anti-Hsp70 antibody levels between women with early- and late-onset PE. However,these antibody levels were high,indicating a strong relationship with the production of HSP60 and Hsp70 protein. CONCLUSION: Association between levels of Hsp70 and uric acid in plasma of patients with early-onset PE seems to reflect the oxidative stress in this group of patients. This study provides evidence that Hsp70 determination may be utilized to assess the differentiation between early- and late-onset PE. FINANCIAL SUPPORT: FAPESP 2010/09241-2.

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INTRODUCTION: Pre-eclampsia (PE) is a complication of human pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. 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. OBJECTIVES: The objective of this study was to assess whether silibinin modulates the activity of NF-kB and the production of inflammatory cytokines by mononuclear cells of patients with PE. METHODS: We evaluated 34 pregnant women with PE, 20 normotensive pregnant women (NT) and 15 non-pregnant women (NP). Mononuclear cells (PBMC) were obtained from peripheral blood and cultured in the presence or absence of silibinin (50uM) and stimulated with 1ug/mL of lipopolysaccharide (LPS) for 18h. The supernatant was employed for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1ß) by enzyme immunoassay. The cells were also cultured for 30min to perform the extraction and determination of the nuclear activity of NF-kB. RESULTS: The results showed increased endogenous activation of NF-kB in PBMC of the PE group compared with the NT and NP groups. We also observed increased production of TNF-α and IL-1ß by non-stimulated PBMC in the PE group compared with NT and NP groups. A positive correlation between NF-kB activity and endogenous production of TNF-α (r=0.6509; p=0.0047) or IL-1 b (r=0.5106; p=0.0304) was observed in the PE group. Silibinin showed an anti-inflammatory activity by inhibiting the spontaneous and LPS-stimulated NF-kB activation as well as the production of inflammatory cytokines in all the groups studied. CONCLUSION: Patients with PE showed a greater activation of PBMC cells compared with NT women. Silibinin showed modulatory activity on the inflammatory response by downregulation of NF-kB activation as well as TNF-α and IL-10 production. FINANCIAL SUPPORT: FAPESP 2010/00776-0.