RESUMO
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
Placenta , Pré-Eclâmpsia , Feminino , Gravidez , Humanos , Gestantes , Pré-Eclâmpsia/genética , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Regulação para Baixo , Serina-Treonina Quinases TOR/metabolismo , Autofagia/fisiologiaRESUMO
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.
RESUMO
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.