The level of circulating exosomal total-miRNA and hsa-miR-210 was elevated in women with PE, and it was higher in the severe form. We showed that hsa-miR-210 is secreted via exosomes, which may have a role in the pathomechanism of the disease.
Introduction: microRNAs (miRNAs) play important role in the regulation of placental development, and abnormal miRNA expression is associated with preeclampsia (PE). miRNAs are released from trophoblast cells to maternal blood flow, where they are highly stable, being encapsulated inside extracellular vesicles, like exosomes or bound to Argonaute proteins. In PE, placental dysfunction leads to aberrant extracellular miRNA secretion. hsa-miR-210 is a hypoxia-sensitive miRNA found to be upregulated in PE, however, it is unknown whether it is the cause or the consequence of the disease. Objective: Our aim was to analyze the expression of several miRNAs, including hsa-miR-210 in placenta, exosome and Ago-bound fractions comparing normal (N) and PE pregnancies. We performed in vitro analyses of extracellular hsa-miR-210 secretion of trophoblast cell cultures (of villous and extravillous origin) under hypoxic condition. Methods: PE and N placenta samples were collected from C-sections, and blood samples were drawn from each pregnant woman in the third trimester. Htr-8 and Jar cell lines were cultured in exosome-free media and treated with hypoxia-mimetic agents. Exosome and Agobound fractions were isolated by membrane affinity spin column method from plasma and cell media. Short RNAs were extracted from exosomes and vesicle-free fractions, and total-RNA was isolated from the placenta samples. The RNA purity and concentration were measured by spectrophotometry. Expression analysis was carried out by qPCR with specific primers to target and reference miRNAs. Results: The level of hsa-miR-210 was significantly higher in PE placentas, which could cause a minor increase of exosomal and a high elevation of Ago-bound miR-210 in circulation. Hypoxia leads to intracellular hsa-miR-210 upregulation in trophoblast cell lines. In extravillous cell (HTR8) media, only the level of exosomal hsa-miR-210 was increased but no change in Ago-bound hsa-miR-210 level was observed. In contrast, in villous cell (JAR) media, the level of exosomal hsa-miR-210 was increased and enhanced release of Ago-bound hsa-miR-210 was also observed. Conclusion: Based on our data, we postulate that in PE, exosomal hsa-miR-210 are secreted actively from the trophoblast, and by intercellular communication, it may have a role in disease etiology. In addition, there is a passive release of Ago-bound hsa-miR-210 into the circulation, which may represent by-products of cell-death and is thereby a possible consequence of the disease.
Intercellular communication via extracellular vesicles (EVs) and their target cells, especially immune cells, results in functional and phenotype changes that consequently may play a significant role in various physiological states and the pathogenesis of immune-mediated disorders. Monocytes are the most prominent environment-sensing immune cells in circulation, skilled to shape their microenvironments via cytokine secretion and further differentiation. Both the circulating monocyte subset distribution and the blood plasma EV pattern are characteristic for preeclampsia, a pregnancy induced immune-mediated hypertensive disorder. We hypothesized that preeclampsia-associated EVs (PE-EVs) induced functional and phenotypic alterations of monocytes. First, we proved EV binding and uptake by THP-1 cells. Cellular origin and protein cargo of circulating PE-EVs were characterized by flow cytometry and mass spectrometry. An altered phagocytosis-associated molecular pattern was found on 12.5 K fraction of PE-EVs: an elevated CD47 “don’t eat me” signal (p < 0.01) and decreased exofacial phosphatidylserine “eat-me” signal (p < 0.001) were found along with decreased uptake of these PE-EVs (p < 0.05). The 12.5 K fraction of PE-EVs induced significantly lower chemotaxis (p < 0.01) and cell motility but accelerated cell adhesion of THP-1 cells (p < 0.05). The 12.5 K fraction of PE-EVs induced altered monocyte functions suggest that circulating EVs may have a role in the pathogenesis of preeclampsia.
BackgroundPravastatin, a known inducer of endothelial nitric-oxide synthase (eNOS) was demonstrated in human placenta, however the exact mechanism of it’s action is not fully understood. Since placental NO (nitric oxide) synthesis is of primary importance in the regulation of placental blood flow, we aimed to clarify the effects of pravastatin on healthy (n = 6) and preeclamptic (n = 6) placentas (Caucasian participants).MethodsThe eNOS activity of human placental microsomes was determined by the conversion rate of C14 L-arginine into C14 L-citrulline with or without pravastatin and Geldanamycin. Phosphorylation of eNOS (Ser1177) was investigated by Western blot. Microsomal arginine uptake was measured by a rapid filtration method.ResultsPravastatin significantly increased total eNOS activity in healthy (28%, p<0.05) and preeclamptic placentas (32%, p<0.05) using 1 mM Ca2+ promoting the dissociation of a eNOS from it’s inhibitor caveolin. Pravastatin and Geldanamycin (Hsp90 inhibitor) cotreatment increased microsomal eNOS activity. Pravastatin treatment had no significant effects on Ser1177 phosphorylation of eNOS in either healthy or preeclamptic placentas. Pravastatin induced arginine uptake of placental microsomes in both healthy (38%, p < 0.05) and preeclamptic pregnancies (34%, p < 0.05).ConclusionsThis study provides a novel mechanism of pravastatin action on placental NO metabolism. Pravastatin induces the placental microsomal arginine uptake leading to the rapid activation of eNOS independently of Ser1177 phosphorylation. These new findings may contribute to better understanding of preeclampsia and may also have a clinical relevance.
A praeeclampsia gyakori és súlyos terhességi kórkép, az anyai és magzati morbiditás és mortalitás egyik vezető oka. A betegség jellemzői a 20. gesztációs hét után kialakult hypertonia és proteinuria, gyakran oedema és több más szubjektív tünet kísérheti. A betegség kiváltó oka a placentában keresendő, a betegség következményei viszont több szervrendszert érintenek. A kétlépcsős modell szerint a placenta kritikus elváltozásai -az abnormális implantá-ció, csökkent lepényi perfúzió -következtében (első lépcső) a keringésbe olyan faktorok kerülnek, amelyek az anyai tünetek megjelenéséért (második lépcső) felelősek. A placenta kórélettanában jelentős szerepet játszik az oxidatív stressz, a nitrogén-monoxid-szintáz enzim csökkent működése, valamint számos sejtes és humorális immunológiai tényező. A manifeszt betegség tüneteinek közös nevezője az endotheldiszfunkció. Az elmélet a hypertonia, proteinuria és oedema triászát és egyéb tünetek eredetét is képes magyarázni. Orv. Hetil., 2012Hetil., , 153, 1167Hetil., -1176 Kulcsszavak: praeeclampsia, nitrogén-monoxid-szintáz, oxidatív stressz, endotheldiszfunkció The pathophysiology of preeclampsia in view of the two-stage modelPreeclampsia is a common and severe disease in pregnancy, a major cause of maternal and fetal morbidity and mortality. The main features of the disease are de novo hypertension after the 20th gestational week and proteinuria, and it is frequently accompanied by edema and other subjective symptoms. The origin of the disease is the placenta, but its sequelae affect multiple organ systems. According to the two-stage model of preeclampsia, the abnormal and hypoperfused placenta (stage 1) releases factors to the bloodstream, which are responsible for the maternal symptoms (stage 2). Oxidative stress, impaired function of nitric-oxide synthase, cellular and humoral immunological factors play an important role in the pathophysiology of the placenta. Endothelial dysfunction is the common denominator of the clinical symptoms. The theory explains the origins of hypertension, proteinuria, edema and other symptoms as well. Orv. Hetil., 2012, 153, 1167-1176 Keywords: preeclampsia, nitric-oxide synthase, oxidative stress, endothelic dysfunction (Beérkezett: 2012. május 16.; elfogadva: 2012. június 7.) Rövidítések ADMA = aszimmetrikus dimetil-arginin; Akt = Akt-kináz, más néven: proteinkináz B (PKB); ASK1 = apoptosis-regulating signal kinase 1; AT1-AA = angiotenzin II 1-es típusú receptorához kötődő agonista hatású antitestek; BH4 = tetrahidrobiopterin; COX = ciklooxigenáz; dNK = decidualis NK-sejt; eNOS = endothelialis nitrogén-monoxid-szintáz; FFA = (free fatty acid) szabad zsírsav; GOT = glutamát/oxálacetát transzamináz; GPT = glutamát/piruvát transzamináz; GTPCH = guanozin-trifoszfát ciklohidroláz; HELLP = haemolyticus anaemia, emelkedett májenzimek, thrombocytopenia; HLA = humán leukocyta-antigén; Hsp90 = hősokkprotein 90; IUGR = intrauterine growth restriction; MAHA = microangiopathiás haemolyticus anaemia; NF-κB = nukleáris faktor kappa-B; PAI = plazminogén...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.