Glucocorticoids modulate multidrug resistance transporters in the first trimester human placenta

The placental multidrug transporters, P‐glycoprotein (P‐gp, encoded by ABCB1) and breast cancer resistance protein (BCRP, ABCG2) protect the foetus from exposure to maternally derived glucocorticoids, toxins and xenobiotics. During pregnancy, maternal glucocorticoid levels can be elevated by stress or exogenous administration. We hypothesized that glucocorticoids modulate the expression of ABCB1/P‐gp and ABCG2/BCRP in the first trimester human placenta. Our objective was to examine whether dexamethasone (DEX) or cortisol modulate first trimester placental expression of multidrug transporters and determine whether cytotrophoblasts or the syncytiotrophoblast are/is responsible for mediating these effects. Three models were examined: (i) an ex‐vivo model of placental villous explants (7‐10 weeks), (ii) a model of isolated first trimester syncytiotrophoblast and cytotrophoblast cells and (iii) the BeWo immortalized trophoblast cell line model. These cells/tissues were treated with DEX or cortisol for 24 hour to 72 hour. In first trimester placental explants, DEX (48 hour) increased ABCB1 (P < .001) and ABCG2 (P < .05) mRNA levels, whereas cortisol (48 hour) only increased ABCB1 mRNA levels (P < .01). Dexamethasone (P < .05) and cortisol (P < .01) increased BCRP but did not affect P‐gp protein levels. Breast cancer resistance protein expression was primarily confined to syncytiotrophoblasts. BeWo cells, when syncytialized with forskolin, increased expression of BCRP protein, and this was further augmented by DEX (P < .05). Our data suggest that the protective barrier provided by BCRP increases as cytotrophoblasts fuse to form the syncytiotrophoblast. Increase in glucocorticoid levels during the first trimester may reduce embryo/foetal exposure to clinically relevant BCRP substrates, because of an increase in placental BCRP.     

First‐trimester blood urea nitrogen and risk of gestational diabetes mellitus

Prior studies indicated that urea increased insulin resistance and higher blood urea nitrogen (BUN) was associated with incident diabetes mellitus. However, it remains unclear whether BUN during the first trimester of pregnancy increases risk of gestational diabetes mellitus (GDM). We aimed to investigate the association between first‐trimester BUN and risk of incident GDM. We conducted a prospective, multicenter cohort study of pregnant women. A total of 13 448 eligible pregnant women with measured first‐trimester BUN levels were included in this analysis. Logistic regression analysis was used to estimate the relationship between BUN and GDM. Discrimination and reclassification for GDM by BUN were analysed. A total of 2973 (22.1%) women developed GDM. Compared with the lowest quartile of BUN, the third and fourth quartiles were associated with increased risk of GDM (adjusted odds ratios 1.21 [95% CI 1.07‐1.37] and 1.50 [95% CI 1.33‐1.69], respectively, P for trend <.001). The addition of BUN to conventional factor model improved discrimination (C statistic 0.2%, P = .003) and reclassification (net reclassification index 14.67%, P < .001; integrated discrimination improvement 0.12%, P < .001) for GDM. In conclusion, higher BUN concentrations during the first trimester of pregnancy were associated with increased risk of GDM, suggesting that BUN could be a potential predictor for GDM.     

Increased immortalization‐upregulated protein 2 (IMUP‐2) by hypoxia induces apoptosis of the trophoblast and pre‐eclampsia

In regulation of the developmental process, the balance between cellular proliferation and cell death is critical. Placental development tightly controls this mechanism, and increased apoptosis of placental trophoblasts can cause a variety of gynecological diseases. Members of the immortalization‐upregulated protein (IMUP) family are nuclear proteins implicated in SV40‐mediated immortalization and cellular proliferation; however, the mechanisms by which their expression is regulated in placental development are still unknown. We compared IMUP‐2 expression in normal and pre‐eclamptic placental tissues and evaluated the function of IMUP‐2 in HTR‐8/SVneo trophoblast cells under hypoxic conditions. IMUP‐2 was expressed in syncytiotrophoblasts and syncytial knots of the placental villi. IMUP‐2 expression was significantly higher in preterm pre‐eclampsia patients than in patients who went to term (P < 0.001); however, we observed no differences in IMUP‐2 expression between normal term patients with and without pre‐eclampsia. Hypoxic conditions increased apoptosis of HTR8/SVneo trophoblast cells and induced IMUP‐2 expression. Also, apoptosis of HTR‐8/SVneo trophoblast cells was increased after IMUP‐2 gene transfection. These results suggest that IMUP‐2 expression is specifically elevated in preterm pre‐eclampsia and under hypoxic conditions, and that IMUP‐2 induces apoptosis of the trophoblast. Therefore, IMUP‐2 might have functional involvement in placental development and gynecological diseases such as pre‐eclampsia. J. Cell. Biochem. 110: 522–530, 2010. © 2010 Wiley‐Liss, Inc.     

17‐AAG suppresses growth and invasion of lung adenocarcinoma cells via regulation of the LATS1/YAP pathway

The large tumour suppressor 1 (LATS1) signalling network has been proved to be an essential regulator within the cell, participating in multiple cellular phenotypes. However, it is unclear concerning the clinical significance of LATS1 and the regulatory mechanisms of 17‐Allylamino‐17‐ demethoxygeldanamycin (17‐AAG) in lung adenocarcinoma (LAC). The aim of the present study was to investigate the correlation of LATS1 and yes‐associated protein (YAP) expression with clinicopathological characteristics in LAC patients, and the effects of 17‐AAG on biological behaviours of LAC cells. Subcutaneous LAC tumour models were further established to observe the tumour growth in nude mice. The results showed that the positive expression of LATS1 was significantly lowered (26.7% versus 68.0%, P < 0.001), while that of YAP was elevated (76.0% versus 56.0%, P = 0.03) in LAC tissues compared to the adjacent non‐cancerous tissues; LAST1 expression was negatively correlated with YAP expression (r = 0.432, P < 0.001) and lymphatic invasion of the tumour (P = 0.015). In addition, 17‐AAG inhibited proliferation and invasion, and induced cell apoptosis and cycle arrest in LAC cells together with increased expression of E‐cadherin and p‐LATS1, and decreased expression of YAP and connective tissue growth factor. Tumour volumes and weight were much smaller in 17‐AAG‐treated groups than those in untreated group (P < 0.01). Taken together, our findings indicate that decreased expression of LATS1 is associated with lymphatic invasion of LAC, and 17‐AAG suppresses growth and invasion of LAC cells via regulation of the LATS1/YAP pathway in vitro and in vivo, suggesting that we may provide a promising therapeutic strategy for the treatment of human LAC.     

Antihypertensive effects of inducible nitric oxide synthase inhibition in experimental pre‐eclampsia

Upregulation of inducible nitric oxide synthase (iNOS) has been reported in both experimental and clinical hypertension. However, although pro‐inflammatory cytokines that up‐regulate iNOS contribute to pre‐eclampsia, no previous study has tested the hypothesis that a selective iNOS inhibitor (1400 W) could exert antihypertensive effects associated with decreased iNOS expression and nitrosative stress in pre‐eclampsia. This study examined the effects of 1400 W in the reduced uteroplacental perfusion pressure (RUPP) placental ischaemia animal model and in normal pregnant rats. Sham‐operated and RUPP rats were treated with daily vehicle or 1 mg/kg/day N‐[3‐(Aminomethyl) benzyl] acetamidine (1400 W) subcutaneously for 5 days. Plasma 8‐isoprostane levels, aortic reactive oxygen species (ROS) levels and nicotinamide adenine dinucleotide phosphate (NADPH)‐dependent ROS production were evaluated by ELISA, dihydroethidium fluorescence microscopy and lucigenin chemiluminescence respectively. Inducible nitric oxide synthase expression was assessed by western blotting analysis and aortic nitrotyrosine was evaluated by immunohistochemistry. Mean arterial blood pressure increased by ~30 mmHg in RUPP rats, and 1400 W attenuated this increase by ~50% (P < 0.05). While RUPP increased plasma 8‐isoprostane levels, aortic ROS levels, and NADPH‐dependent ROS production (P < 0.05), treatment with 1400 W blunted these alterations (P < 0.05). Moreover, while RUPP increased iNOS expression and aortic nitrotyrosine levels (P < 0.05), treatment with 1400 W blunted these alterations (P < 0.05). These results clearly implicate iNOS in the hypertension associated with RUPP. Our findings may suggest that iNOS inhibitors could be clinically useful in the therapy of pre‐eclampsia, especially in particular groups of patients genetically more prone to express higher levels of iNOS. This issue deserves further confirmation.     

Down-regulation of placental folate transporters in intrauterine growth restriction

Folate deficiency in pregnancy is associated with neural tube defects, restricted fetal growth and fetal programming of diseases later in life. Fetal folate availability is dependent on maternal folate levels and placental folate transport capacity, mediated by two key transporters, Folate Receptor-α and Reduced Folate Carrier (RFC). We tested the hypothesis that intrauterine growth restriction (IUGR) is associated with decreased folate transporter expression and activity in isolated syncytiotrophoblast microvillous plasma membranes (MVM). Women with pregnancies complicated by IUGR (birth weight <3rd percentile, mean birth weight 1804±110 g, gestational age 35.7±0.61 weeks, n=25) and women delivering an appropriately-for gestational age infant (control group, birth weight 25th–75th centile, mean birth weight 2493±216 g, gestational age 33.9±0.95 weeks, n=19) were recruited and placentas were collected at delivery. MVM was isolated and folate transporter protein expression was measured using Western blot and transporter activity was determined using radiolabelled methyltetrahydrofolic acid and rapid filtration. Whereas the expression of FR-α was unaffected, MVM RFC protein expression was significantly decreased in the IUGR group (−34%, P<.05). IUGR MVM had a significantly lower folate uptake compared to the control group (−38%, P<.05). In conclusion, placental folate transport capacity is decreased in IUGR, which may contribute to the restricted fetal growth and intrauterine programming of childhood and adult disease. These findings suggest that continuation of folate supplementation in the second and third trimester is of particular importance in pregnancies complicated by IUGR.     

Loss of retinal ganglion cells in a new genetic mouse model for primary open‐angle glaucoma

Primary open‐angle glaucoma (POAG) is one of the most common causes for blindness worldwide. Although an elevated intraocular pressure (IOP) is the main risk factor, the exact pathology remained indistinguishable. Therefore, it is necessary to have appropriate models to investigate these mechanisms. Here, we analysed a transgenic glaucoma mouse model (βB1‐CTGF) to elucidate new possible mechanisms of the disease. Therefore, IOP was measured in βB1‐CTGF and wildtype mice at 5, 10 and 15 weeks of age. At 5 and 10 weeks, the IOP in both groups were comparable (P > 0.05). After 15 weeks, a significant elevated IOP was measured in βB1‐CTGF mice (P < 0.001). At 15 weeks, electroretinogram measurements were performed and both the a‐ and b‐wave amplitudes were significantly decreased in βB1‐CTGF retinae (both P < 0.01). Significantly fewer Brn‐3a⁺ retinal ganglion cells (RGCs) were observed in the βB1‐CTGF group on flatmounts (P = 0.02), cross‐sections (P < 0.001) and also via quantitative real‐time PCR (P = 0.02). Additionally, significantly more cleaved caspase 3⁺ RGCs were seen in the βB1‐CTGF group (P = 0.002). Furthermore, a decrease in recoverin⁺ cells was observable in the βB1‐CTGF animals (P = 0.004). Accordingly, a significant down‐regulation of Recoverin mRNA levels were noted (P < 0.001). Gfap expression, on the other hand, was higher in βB1‐CTGF retinae (P = 0.023). Additionally, more glutamine synthetase signal was noted (P = 0.04). Although no alterations were observed regarding photoreceptors via immunohistology, a significant decrease of Rhodopsin (P = 0.003) and Opsin mRNA (P = 0.03) was noted. We therefore assume that the βB1‐CTGF mouse could serve as an excellent model for better understanding the pathomechanisms in POAG.     

Inhibition of infection‐mediated preterm birth by administration of broad spectrum chemokine inhibitor in mice

Preterm birth (PTB) is the single most important cause of perinatal and infant mortality worldwide. Maternal infection can result in PTB. We investigated the ability of a Broad Spectrum Chemokine Inhibitor (BSCI) to prevent infection‐induced PTB in mice. PTB was initiated in pregnant mice by intraperitoneal injection of lipopolysaccharide (LPS; 50 μg). Half the mice received BSCI (10 mg/kg) 24 hrs prior to and immediately before LPS administration. The impact of LPS alone or LPS plus BSCI was assessed on (i) injection‐to‐delivery interval, foetal survival rate, placental and neonates' weight; (ii) amniotic fluid and maternal plasma cytokine levels (by Luminex assay); foetal and maternal tissue cytokine gene expression levels (by Real‐Time RT‐PCR); (iii) immune cells infiltration into the uterine tissue (by stereological immunohistochemistry). Pre‐treatment with BSCI (i) decreased LPS‐induced PTB (64% versus 100%, P < 0.05); (ii) significantly attenuated cytokine/chemokine expression in maternal tissues (plasma, liver, myometrium, decidua); (iii) significantly decreased neutrophil infiltration in the mouse myometrium. BSCI‐treated mice in which PTB was delayed till term had live foetuses with normal placental and foetal weight. BSCI represents a promising new class of therapeutics for PTB. In a mouse model of preterm labour, BCSI suppresses systemic inflammation in maternal tissues which resulted in the reduced incidence of LPS‐mediated PTB. These data provide support for efforts to target inflammatory responses as a means of preventing PTB.     

Identification of a 4‐mRNA metastasis‐related prognostic signature for patients with breast cancer

Metastasis‐related mRNAs have showed great promise as prognostic biomarkers in various types of cancers. Therefore, we attempted to develop a metastasis‐associated gene signature to enhance prognostic prediction of breast cancer (BC) based on gene expression profiling. We firstly screened and identified 56 differentially expressed mRNAs by analysing BC tumour tissues with and without metastasis in the discovery cohort (GSE102484, n = 683). We then found 26 of these differentially expressed genes were associated with metastasis‐free survival (MFS) in the training set (GSE20685, n = 319). A metastasis‐associated gene signature built using a LASSO Cox regression model, which consisted of four mRNAs, can classify patients into high‐ and low‐risk groups in the training cohort. Patients with high‐risk scores in the training cohort had shorter MFS (hazard ratio [HR] 3.89, 95% CI 2.53‐5.98; P < 0.001), disease‐free survival (DFS) (HR 4.69, 2.93‐7.50; P < 0.001) and overall survival (HR 4.06, 2.56‐6.45; P < 0.001) than patients with low‐risk scores. The prognostic accuracy of mRNAs signature was validated in the two independent validation cohorts (GSE21653, n = 248; GSE31448, n = 246). We then developed a nomogram based on the mRNAs signature and clinical‐related risk factors (T stage and N stage) that predicted an individual's risk of disease, which can be assessed by calibration curves. Our study demonstrated that this 4‐mRNA signature might be a reliable and useful prognostic tool for DFS evaluation and will facilitate tailored therapy for BC patients at different risk of disease.     

Protective effect of heme oxygenase induction in ethinylestradiol‐induced cholestasis

Estrogen‐induced cholestasis is characterized by impaired hepatic uptake and biliary bile acids secretion because of changes in hepatocyte transporter expression. The induction of heme oxygenase‐1 (HMOX1), the inducible isozyme in heme catabolism, is mediated via the Bach1/Nrf2 pathway, and protects livers from toxic, oxidative and inflammatory insults. However, its role in cholestasis remains unknown. Here, we investigated the effects of HMOX1 induction by heme on ethinylestradiol‐induced cholestasis and possible underlying mechanisms. Wistar rats were given ethinylestradiol (5 mg/kg s.c.) for 5 days. HMOX1 was induced by heme (15 μmol/kg i.p.) 24 hrs prior to ethinylestradiol. Serum cholestatic markers, hepatocyte and renal membrane transporter expression, and biliary and urinary bile acids excretion were quantified. Ethinylestradiol significantly increased cholestatic markers (P ≤ 0.01), decreased biliary bile acid excretion (39%, P = 0.01), down‐regulated hepatocyte transporters (Ntcp/Oatp1b2/Oatp1a4/Mrp2, P ≤ 0.05), and up‐regulated Mrp3 (348%, P ≤ 0.05). Heme pre‐treatment normalized cholestatic markers, increased biliary bile acid excretion (167%, P ≤ 0.05) and up‐regulated hepatocyte transporter expression. Moreover, heme induced Mrp3 expression in control (319%, P ≤ 0.05) and ethinylestradiol‐treated rats (512%, P ≤ 0.05). In primary rat hepatocytes, Nrf2 silencing completely abolished heme‐induced Mrp3 expression. Additionally, heme significantly increased urinary bile acid clearance via up‐regulation (Mrp2/Mrp4) or down‐regulation (Mrp3) of renal transporters (P ≤ 0.05). We conclude that HMOX1 induction by heme increases hepatocyte transporter expression, subsequently stimulating bile flow in cholestasis. Also, heme stimulates hepatic Mrp3 expression via a Nrf2‐dependent mechanism. Bile acids transported by Mrp3 to the plasma are highly cleared into the urine, resulting in normal plasma bile acid levels. Thus, HMOX1 induction may be a potential therapeutic strategy for the treatment of ethinylestradiol‐induced cholestasis.     

Triamcinolone up‐regulates GLUT 1 and GLUT 3 expression in cultured human placental endothelial cells

The placenta is a glucocorticoid target organ, and glucocorticoids (GCs) are essential for the development and maturation of fetal organs. They are widely used for treatment of a variety of diseases during pregnancy. In various tissues, GCs have regulated by glucose transport systems; however, their effects on glucose transporters in the human placental endothelial cells (HPECs) are unknown. In the present study, HPECs were cultured 24 h in the presence or absence of 0·5, 5 and 50 µmol·l^–1 of synthetic GC triamcinolone (TA). The glucose carrier proteins GLUT 1, GLUT 3 and GC receptor (GR) were detected in the HPECs. We showed increased expression of GLUT 1 and GLUT 3 proteins and messenger RNA (mRNA) levels (p < 0·05) after 24‐h cell culture in the presence of 0·5, 5 and 50 µmol·l^‐1 of TA. In contrast, GR protein and mRNA expressions were down‐regulated (p < 0·05) with 0·5, 5 and 50 µmol·l^–1 of TA 24‐h cell culture. The results demonstrate that GCs are potent regulators of placental GLUT 1 and GLUT 3 expression through GR. Excessive exposure to GCs causes maternal and fetal hypoglycemia and diminished fetal growth. We speculate that to compensate for fetal hypoglycemia and diminished fetal growth, the expression of placental endothelial glucose transporters might be increased. Copyright © 2011 John Wiley & Sons, Ltd.     

Dietary rapamycin supplementation reverses age‐related vascular dysfunction and oxidative stress,while modulating nutrient‐sensing,cell cycle,and senescence pathways

Inhibition of mammalian target of rapamycin, mTOR, extends lifespan and reduces age‐related disease. It is not known what role mTOR plays in the arterial aging phenotype or if mTOR inhibition by dietary rapamycin ameliorates age‐related arterial dysfunction. To explore this, young (3.8 ± 0.6 months) and old (30.3 ± 0.2 months) male B6D2F1 mice were fed a rapamycin supplemented or control diet for 6–8 weeks. Although there were few other notable changes in animal characteristics after rapamycin treatment, we found that glucose tolerance improved in old mice, but was impaired in young mice, after rapamycin supplementation (both P < 0.05). Aging increased mTOR activation in arteries evidenced by elevated S6K phosphorylation (P < 0.01), and this was reversed after rapamycin treatment in old mice (P < 0.05). Aging was also associated with impaired endothelium‐dependent dilation (EDD) in the carotid artery (P < 0.05). Rapamycin improved EDD in old mice (P < 0.05). Superoxide production and NADPH oxidase expression were higher in arteries from old compared to young mice (P < 0.05), and rapamycin normalized these (P < 0.05) to levels not different from young mice. Scavenging superoxide improved carotid artery EDD in untreated (P < 0.05), but not rapamycin‐treated, old mice. While aging increased large artery stiffness evidenced by increased aortic pulse‐wave velocity (PWV) (P < 0.01), rapamycin treatment reduced aortic PWV (P < 0.05) and collagen content (P < 0.05) in old mice. Aortic adenosine monophosphate‐activated protein kinase (AMPK) phosphorylation and expression of the cell cycle‐related proteins PTEN and p27kip were increased with rapamycin treatment in old mice (all P < 0.05). Lastly, aging resulted in augmentation of the arterial senescence marker, p19 (P < 0.05), and this was ameliorated by rapamycin treatment (P < 0.05). These results demonstrate beneficial effects of rapamycin treatment on arterial function in old mice and suggest these improvements are associated with reduced oxidative stress, AMPK activation and increased expression of proteins involved in the control of the cell cycle.     

Regulation of laryngeal squamous cell cancer progression by the lncRNA RP11‐159K7.2/miR‐206/DNMT3A axis

Long non‐coding RNAs (lncRNAs), which are longer than 200 nt, have been proved to play a role in promoting or inhibiting cancer progression. The following study investigated the role and underlying mechanisms of lncRNA RP11‐159K7.2 in laryngeal squamous cell carcinoma (LSCC) progression. Briefly, in situ hybridization (ISH) and real‐time quantitative PCR (RT‐qPCR) showed higher expression of RP11‐159K7.2 in LSCC tissues and cell lines. Patients with low expression level of RP11‐159K7.2 lived longer compared to those with high expression of RP11‐159K7.2 (χ² = 39.111, ***P < 0.001). Multivariate Cox regression analysis suggested that lncRNA RP11‐159K7.2 was an independent prognostic factor for LSCC patients (HR = 2.961, ***P < 0.001). Furthermore, to investigate the potential involvement of RP11‐159K7.2 in the development of LSCC, we knocked out the expression of endogenous RP11‐159K7.2 in TU‐212 cells and AMC‐HN‐8 cells via CRISPR/Cas9 double vector lentiviral system. RP11‐159K7.2 knockout decreased LSCC cell growth and invasion both in vitro and in vivo. Mechanically, we found that RP11‐159K7.2 could positively regulate the expression of DNMT3A by sponging miR‐206. In addition, a feedback loop was also discovered between DNMT3A and miR‐206. To sum up, these findings suggest that lncRNA RP11‐159K7.2 could be used as a potential biomarker for prognosis and treatment of LSCC.     

Spermatogonial stem cell sensitivity to capsaicin: An in vitro study

Background

The placenta is an important site for iron metabolism in humans. It transfers iron from the mother to the fetus. One of the major iron transport proteins is transferrin, which is a blood plasma protein crucial for iron uptake. Its localization and expression may be one of the markers to distinguish placental dysfunction.

Methods

In the experimental study we used antibody preparation, mass spectrometric analysis, biochemical and immunocytochemical methods for characterization of transferrin expression on the human choriocarcinoma cell line JAR (JAR cells), placental lysates, and cryostat sections. Newly designed monoclonal antibody TRO-tf-01 to human transferrin was applied on human placentae from normal (n = 3) and abnormal (n = 9) pregnancies.

Results

Variations of transferrin expression were detected in villous syncytiotrophoblast, which is in direct contact with maternal blood. In placentae from normal pregnancies, the expression of transferrin in the syncytium was significantly lower (p < 0.001) when compared to placentae from abnormal ones (gestational diabetes, pregnancy induced hypertension, drug abuse).

Conclusion

These observations suggest that in the case of abnormal pregnancies, the fetus may require higher levels of transferrin in order to prevent iron depletion due to the stress from the placental dysfunction.     

The Role of Pro- and Antioxidant Systems in the Development of Placental Dysfunction in Human Pregnancy

The pro-and antioxidant systems of the human placenta have been studied in its central and peripheral areas in the state of dysfunction. It has been shown that the intensity of free-radical oxidation (FRO) is 24% higher (p < 0.05) in mitochondria isolated from peripheral placental areas in the case of preterm termination of pregnancy than in placental mitochondria of women with normal pregnancy ending in delivery on due dates. The values of total antioxidant activity in mitochondria isolated from the central and peripheral areas of placentae of women with preterm labor exceeded 1.5-and 1.8-fold the respective values for the placental mitochondria of women with the normal duration of pregnancy. The rate of glutathione peroxidase activity in placental mitochondria of women with preterm labor was lower than in patients with normal duration of pregnancy terminated on due dates. Higher values of intensity of both the FRO processes and the active components of thiobarbituric acid (TBA) were recorded (higher by 42% and 62%, respectively) in the postmitochondrial fraction in the peripheral area of placentae of women with spontaneous termination of pregnancy, compared with the placentae of women with uncomplicated duration of pregnancy with labor on due date. No differences have been observed in the intensity of oxidative modification of placental proteins in both the periphery and the center in the placentae of women from the studied groups. The rate of glutathione peroxidase activity in the placenta of women with spontaneous termination of pregnancy was more than twice as high as the activity of this enzyme during the first trimester of normal pregnancy and remained high during the second and third trimesters. The activity of the enzyme did not depend on its localization (center or periphery) in placentae of women participating in the study. The values of glutathione transferase activity in the placentae increased in the course of normal pregnancy but remained at the level of the first trimester in the central and peripheral areas in the case of a miscarriage at different gestational terms. Our findings allow us to suggest that oxidative stress developing in placenta from its center to periphery plays a key role in the pathogenesis of placental dysfunction, mainly, due to the glutathione-dependent component of the placental antioxidant defense.     

Mitochondrial toxicity and caspase activation in HIV pregnant women

To assess the impact of HIV‐infection and highly active anti‐retroviral treatment in mitochondria and apoptotic activation of caspases during pregnancy and their association with adverse perinatal outcome. Changes of mitochondrial parameters and apoptotic caspase activation in maternal peripheral blood mononuclear cells were compared at first trimester of pregnancy and delivery in 27 HIV‐infected and ‐treated pregnant women versus 24 uninfected pregnant controls. We correlated immunovirological, therapeutic and perinatal outcome with experimental findings: mitochondrial DNA (mtDNA) content, mitochondrial protein synthesis, mitochondrial function and apoptotic caspase activation. The HIV pregnancies showed increased adverse perinatal outcome (OR: 4.81 [1.14–20.16]; P < 0.05) and decreased mtDNA content (42.66 ± 5.94%, P < 0.01) compared to controls, even higher in naïve participants. This depletion caused a correlated decrease in mitochondrial protein synthesis (12.82 ± 5.73%, P < 0.01) and function (20.50 ± 10.14%, P < 0.001), not observed in controls. Along pregnancy, apoptotic caspase‐3 activation increased 63.64 ± 45.45% in controls (P < 0.001) and 100.00 ± 47.37% in HIV‐pregnancies (P < 0.001), in correlation with longer exposure to nucleoside analogues. HIV‐infected women showed increased obstetric problems and declined genetic and functional mitochondrial parameters during pregnancy, especially those firstly exposed to anti‐retrovirals. The apoptotic activation of caspases along pregnancy is emphasized in HIV pregnancies promoted by nucleoside analogues. However, we could not demonstrate direct mitochondrial or apoptotic implication in adverse obstetric outcome probably because of the reduced sample size.