Pharmacoproteomics pinpoints HSP70 interaction for correction of the most frequent Wilson disease-causing mutant of ATP7B.

Pathogenic mutations in the copper transporter ATP7B have been hypothesized to affect its protein interaction landscape contributing to loss of function and, thereby, to hepatic copper toxicosis in Wilson disease. Although targeting mutant interactomes was proposed as a therapeutic strategy, druggable interactors for rescue of ATP7B mutants remain elusive. Using proteomics, we found that the frequent H1069Q substitution promotes ATP7B interaction with HSP70, thus accelerating endoplasmic reticulum (ER) degradation of the mutant protein and consequent copper accumulation in hepatic cells. This prompted us to use an HSP70 inhibitor as bait in a bioinformatics search for structurally similar Food and Drug Administration-approved drugs. Among the hits, domperidone emerged as an effective corrector that recovered trafficking and function of ATP7B-H1069Q by impairing its exposure to the HSP70 proteostatic network. Our findings suggest that HSP70-mediated degradation can be safely targeted with domperidone to rescue ER-retained ATP7B mutants and, hence, to counter the onset of Wilson disease.

Hmga2 protein loss alters nuclear envelope and 3D chromatin structure.

BACKGROUND: The high-mobility group Hmga family of proteins are non-histone chromatin-interacting proteins which have been associated with a number of nuclear functions, including heterochromatin formation, replication, recombination, DNA repair, transcription, and formation of enhanceosomes. Due to its role based on dynamic interaction with chromatin, Hmga2 has a pathogenic role in diverse tumors and has been mainly studied in a cancer context; however, whether Hmga2 has similar physiological functions in normal cells remains less explored. Hmga2 was additionally shown to be required during the exit of embryonic stem cells (ESCs) from the ground state of pluripotency, to allow their transition into epiblast-like cells (EpiLCs), and here, we use that system to gain further understanding of normal Hmga2 function. RESULTS: We demonstrated that Hmga2 KO pluripotent stem cells fail to develop into EpiLCs. By using this experimental system, we studied the chromatin changes that take place upon the induction of EpiLCs and we observed that the loss of Hmga2 affects the histone mark H3K27me3, whose levels are higher in Hmga2 KO cells. Accordingly, a sustained expression of polycomb repressive complex 2 (PRC2), responsible for H3K27me3 deposition, was observed in KO cells. However, gene expression differences between differentiating wt vs Hmga2 KO cells did not show any significant enrichments of PRC2 targets. Similarly, endogenous Hmga2 association to chromatin in epiblast stem cells did not show any clear relationships with gene expression modification observed in Hmga2 KO. Hmga2 ChIP-seq confirmed that this protein preferentially binds to the chromatin regions associated with nuclear lamina. Starting from this observation, we demonstrated that nuclear lamina underwent severe alterations when Hmga2 KO or KD cells were induced to exit from the naïve state and this phenomenon is accompanied by a mislocalization of the heterochromatin mark H3K9me3 within the nucleus. As nuclear lamina (NL) is involved in the organization of 3D chromatin structure, we explored the possible effects of Hmga2 loss on this phenomenon. The analysis of Hi-C data in wt and Hmga2 KO cells allowed us to observe that inter-TAD (topologically associated domains) interactions in Hmga2 KO cells are different from those observed in wt cells. These differences clearly show a peculiar compartmentalization of inter-TAD interactions in chromatin regions associated or not to nuclear lamina. CONCLUSIONS: Overall, our results indicate that Hmga2 interacts with heterochromatic lamin-associated domains, and highlight a role for Hmga2 in the crosstalk between chromatin and nuclear lamina, affecting the establishment of inter-TAD interactions.

YAP contributes to DNA methylation remodeling upon mouse embryonic stem cell differentiation.

The Yes-associated protein (YAP), one of the major effectors of the Hippo pathway together with its related protein WW-domain-containing transcription regulator 1 (WWTR1; also known as TAZ), mediates a range of cellular processes from proliferation and death to morphogenesis. YAP and WW-domain-containing transcription regulator 1 (WWTR1; also known as TAZ) regulate a large number of target genes, acting as coactivators of DNA-binding transcription factors or as negative regulators of transcription by interacting with the nucleosome remodeling and histone deacetylase complexes. YAP is expressed in self-renewing embryonic stem cells (ESCs), although it is still debated whether it plays any crucial roles in the control of either stemness or differentiation. Here we show that the transient downregulation of YAP in mouse ESCs perturbs cellular homeostasis, leading to the inability to differentiate properly. Bisulfite genomic sequencing revealed that this transient knockdown caused a genome-wide alteration of the DNA methylation remodeling that takes place during the early steps of differentiation, suggesting that the phenotype we observed might be due to the dysregulation of some of the mechanisms involved in regulation of ESC exit from pluripotency. By gene expression analysis, we identified two molecules that could have a role in the altered genome-wide methylation profile: the long noncoding RNA ephemeron, whose rapid upregulation is crucial for the transition of ESCs into epiblast, and the methyltransferase-like protein Dnmt3l, which, during the embryo development, cooperates with Dnmt3a and Dnmt3b to contribute to the de novo DNA methylation that governs early steps of ESC differentiation. These data suggest a new role for YAP in the governance of the epigenetic dynamics of exit from pluripotency.

Vasa previa: when antenatal diagnosis can change fetal prognosis.

OBJECTIVES: Evaluate ultrasound diagnostic accuracy, maternal-fetal characteristics and outcomes in case of vasa previa diagnosed antenatally, postnatally or with spontaneous resolution before delivery. METHODS: Monocentric retrospective study enrolling women with antenatal or postnatal diagnosis of vasa previa at Sant'Anna Hospital in Turin from 2007 to 2018. Vasa previa were defined as fetal vessels that lay 2 cm within the uterine internal os using 2D and Color Doppler transvaginal ultrasound. Diagnosis was confirmed at delivery and on histopathological exam. Vasa previa with spontaneous resolutions were defined as fetal vessels that migrate >2 cm from uterine internal os during scheduled ultrasound follow-ups in pregnancy. RESULTS: We enrolled 29 patients (incidence of 0.03%). Ultrasound antenatally diagnosed 25 vasa previa (five had a spontaneous resolution) while four were diagnosed postnatally, with an overall sensitivity of 96.2%, specificity of 100%, positive predictive value of 96.2%, and negative predictive value of 100%. Early gestational age at diagnosis is significally associate with spontaneously resolution (p 0.023; aOR 1.63; 95% IC 1.18-2.89). Nearly 93% of our patient had a risk factor for vasa previa: placenta previa at second trimester or low-lying placenta, bilobated placenta, succenturiate cotyledon, velametous cord insertion or assisted reproduction technologies. CONCLUSIONS: Maternal and fetal outcomes in case of vasa previa antenatally diagnosed are significally improved. Our data support the evaluation of umbilical cord insertion during routine second trimester ultrasound and a targeted screening for vasa previa in women with risk factor: it allows identification of fetus at high risk, reducing fetal mortality in otherwise healthy newborns.

Traditional McCall culdoplasty compared to a modified McCall technique with double ligament suspension: anatomical and clinical outcomes.

INTRODUCTION AND HYPOTHESIS: This study compared anatomical and clinical outcomes of traditional McCall culdoplasty versus a modified McCall technique with double ligament suspension (DLS). METHODS: This retrospective study presents outcomes of 68 patients who underwent vaginal hysterectomy and vaginal suspension for apical prolapse ≥ stage II according to the POP-Q score system, at, between January 2016 and February 2018. In 34 women vaginal cuff suspension was obtained with traditional McCall culdoplasty (McCall group), while in 34 women we performed a modified McCall, which consists of a double ligament suspension (DLS group), suspending the vaginal cuff to uterosacral ligaments and also to adnexal peduncles. Primary outcome was prolapse recurrence ≥ stage II according to the POP-Q system. Fisher's, Mann-Whitney U and Student's t tests were used for statistical analysis. RESULTS: There were no statistical differences among patients' preoperative characteristics, operative time, blood loss or postoperative complications. Follow-up mean duration was 23.2 ± 6.7 and 22.4 ± 8.7 months in the McCall and DLS group, respectively. Prolapse recurrence occurred in 11 (32.3%) women in the McCall group versus 2 (5.9%) women in the DLS group (p < 0.05): among them, 2 patients (5.9%) in the McCall group and 1 (2.9%) in the DLS group required further treatment. Total vaginal length was 6.1 ± 0.9 cm in the McCall group versus 6.9 ± 0.7 cm in the DLS group (p < 0.001). No statistical difference in quality of life assessment was observed. CONCLUSIONS: DLS group patients had better anatomical outcomes and lower recurrence rates than McCall group patients, without increasing operative time or complications. A prospective study with more cases is needed to confirm our data.

Arteriovenous uterine malformation developed from an interstitial pregnancy on residual tubal stump: A critical managment in a fertile woman.

Uterine arteriovenous malformations are rare conditions with diverse clinical presentation that range from asymptomatic patients to different degrees of menorrhagia, commonly associated with previous pregnancy or uterine trauma. This case report describes a 36-year-old woman who presented with ultrasound diagnosis of interstitial pregnancy on residual right tube stump 4 months after a laparoscopic salpingectomy for extrauterine pregnancy. She started treatment with methotrexate; afterwards serum human chorionic gonadotropin levels and ultrasound follow-ups were scheduled. While serum human chorionic gonadotropin levels were progressively reducing, transvaginal ultrasound follow-ups showed a persistent anechoic mass on right rube stump, with increased peripheral high flow vascularity: highly suspicious for a uterine arteriovenous malformation. A laparoscopy was performed with a tumorectomy of the mass. The histopathological exam of the specimen confirmed uterine arteriovenous malformation. Patient successfully became pregnant 2 years later, with an eventless pregnancy and a vaginal delivery without complications.

The Key Role of MicroRNAs in Self-Renewal and Differentiation of Embryonic Stem Cells.

Naïve pluripotent embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs) represent distinctive developmental stages, mimicking the pre- and the post-implantation events during the embryo development, respectively. The complex molecular mechanisms governing the transition from ESCs into EpiSCs are orchestrated by fluctuating levels of pluripotency transcription factors (Nanog, Oct4, etc.) and wide-ranging remodeling of the epigenetic landscape. Recent studies highlighted the pivotal role of microRNAs (miRNAs) in balancing the switch from self-renewal to differentiation of ESCs. Of note, evidence deriving from miRNA-based reprogramming strategies underscores the role of the non-coding RNAs in the induction and maintenance of the stemness properties. In this review, we revised recent studies concerning the functions mediated by miRNAs in ESCs, with the aim of giving a comprehensive view of the highly dynamic miRNA-mediated tuning, essential to guarantee cell cycle progression, pluripotency maintenance and the proper commitment of ESCs.

HMGA Proteins in Stemness and Differentiation of Embryonic and Adult Stem Cells.

HMGA1 and HMGA2 are chromatin architectural proteins that do not have transcriptional activity per se, but are able to modify chromatin structure by interacting with the transcriptional machinery and thus negatively or positively regulate the transcription of several genes. They have been extensively studied in cancer where they are often found to be overexpressed but their functions under physiologic conditions have still not been completely addressed. Hmga1 and Hmga2 are expressed during the early stages of mouse development, whereas they are not detectable in most adult tissues. Hmga overexpression or knockout studies in mouse have pointed to a key function in the development of the embryo and of various tissues. HMGA proteins are expressed in embryonic stem cells and in some adult stem cells and numerous experimental data have indicated that they play a fundamental role in the maintenance of stemness and in the regulation of differentiation. In this review, we discuss available experimental data on HMGA1 and HMGA2 functions in governing embryonic and adult stem cell fate. Moreover, based on the available evidence, we will aim to outline how HMGA expression is regulated in different contexts and how these two proteins contribute to the regulation of gene expression and chromatin architecture in stem cells.

APP Maturation and Intracellular Localization Are Controlled by a Specific Inhibitor of 37/67 kDa Laminin-1 Receptor in Neuronal Cells.

Amyloid precursor protein (APP) is processed along both the nonamyloidogenic pathway preventing amyloid beta peptide (Aß) production and the amyloidogenic pathway, generating Aß, whose accumulation characterizes Alzheimer's disease. Items of evidence report that the intracellular trafficking plays a key role in the generation of Aß and that the 37/67 kDa LR (laminin receptor), acting as a receptor for Aß, may mediate Aß-pathogenicity. Moreover, findings indicating interaction between the receptor and the key enzymes involved in the amyloidogenic pathway suggest a strong link between 37/67 kDa LR and APP processing. We show herein that the specific 37/67 kDa LR inhibitor, NSC48478, is able to reversibly affect the maturation of APP in a pH-dependent manner, resulting in the partial accumulation of the immature APP isoforms (unglycosylated/acetylated forms) in the endoplasmic reticulum (ER) and in transferrin-positive recycling endosomes, indicating alteration of the APP intracellular trafficking. These effects reveal NSC48478 inhibitor as a novel small molecule to be tested in disease conditions, mediated by the 37/67 kDa LR and accompanied by inactivation of ERK1/2 (extracellular signal-regulated kinases) signalling and activation of Akt (serine/threonine protein kinase) with consequent inhibition of GSK3ß.

Pluripotent stem cell-derived bile canaliculi-forming hepatocytes to study genetic liver diseases involving hepatocyte polarity.

BACKGROUND & AIMS: Hepatocyte polarity is essential for the development of bile canaliculi and for safely transporting bile and waste products from the liver. Functional studies of autologous mutated proteins in the context of the polarized hepatocyte have been challenging because of the lack of appropriate cell models. The aims of this study were to obtain a patient-specific hepatocyte model that recapitulated hepatocyte polarity and to employ this model to study endogenous mutant proteins in liver diseases that involve hepatocyte polarity. METHODS: Urine cell-derived pluripotent stem cells, taken from a patient with a homozygous mutation in ATP7B and a patient with a heterozygous mutation, were differentiated towards hepatocyte-like cells (hiHeps). HiHeps were also derived from a patient with MEDNIK syndrome. RESULTS: Polarized hiHeps that formed in vivo-like bile canaliculi could be generated from embryonic and patient urine cell-derived pluripotent stem cells. HiHeps recapitulated polarized protein trafficking processes, exemplified by the Cu2+-induced redistribution of the copper transporter protein ATP7B to the bile canalicular domain. We demonstrated that, in contrast to the current dogma, the most frequent yet enigmatic Wilson disease-causing ATP7B-H1069Q mutation per se did not preclude trafficking of ATP7B to the trans-Golgi Network. Instead, it prevented its Cu2+-induced polarized redistribution to the bile canalicular domain, which could not be reversed by pharmacological folding chaperones. Finally, we demonstrate that hiHeps from a patient with MEDNIK syndrome, suffering from liver copper overload of unclear etiology, showed no defect in the Cu2+-induced redistribution of ATP7B to the bile canaliculi. CONCLUSIONS: Functional cell polarity can be achieved in patient pluripotent stem cell-derived hiHeps, enabling, for the first time, the study of the endogenous mutant proteins, patient-specific pathogenesis and drug responses for diseases where hepatocyte polarity is a key factor. LAY SUMMARY: This study demonstrates that cells that are isolated from urine can be reprogrammed in a dish towards hepatocytes that display architectural characteristics similar to those seen in the intact liver. The application of this methodology to cells from patients diagnosed with inherited copper metabolism-related liver diseases (that is, Wilson disease and MEDNIK syndrome) revealed unexpected and novel insights into patient mutation-specific disease mechanisms and drug responses.

Insights into the pathogenesis of ATP1A1-related CMT disease using patient-specific iPSCs.

The development of patient-specific induced pluripotent stem cells (iPSCs) offered interesting insights in modeling the pathogenesis of Charcot-Marie-Tooth (CMT) disease and thus we decided to explore the phenotypes of iPSCs derived from a single CMT patient carrying a mutant ATP1A1 allele (p.Pro600Ala). iPSCs clones generated from CMT and control fibroblasts, were induced to differentiate into neural precursors and then into post-mitotic neurons. Control iPSCs differentiated into neuronal precursors and then into post-mitotic neurons within 6-8 days. On the contrary, the differentiation of CMT iPSCs was clearly defective. Electrophysiological properties confirmed that post-mitotic neurons were less mature compared to the normal counterpart. The impairment of in vitro differentiation of CMT iPSCs only concerned with the neuronal pathway, because they were able to differentiate into mesendodermal cells and other ectodermal derivatives. ATP1A1 was undetectable in the few neuronal cells derived from CMT iPSCs. ATP1A1 gene mutation (p.Pro600Ala), responsible for a form of axonal CMT disease, is associated in vitro with a dramatic alteration of the differentiation of patient-derived iPSCs into post-mitotic neurons. Thus, the defect in neuronal cell development might lead in vivo to a decreased number of mature neurons in ATP1A1-CMT disease.

Lin28 is induced in primed embryonic stem cells and regulates let-7-independent events.

Lin28 RNA-binding proteins play important roles in pluripotent stem cells, but the regulation of their expression and the mechanisms underlying their functions are still not definitively understood. Here we address the above-mentioned issues in the first steps of mouse embryonic stem cell (ESC) differentiation. We observed that the expression of Lin28 genes is transiently induced soon after the exit of ESCs from the naive ground state and that this induction is due to the Hmga2-dependent engagement of Otx2 with enhancers present at both Lin28 gene loci. These mechanisms are crucial for Lin28 regulation, as demonstrated by the abolishment of the Lin28 accumulation in Otx2- or Hmga2-knockout cells compared to the control cells. We have also found that Lin28 controls Hmga2 expression levels during ESC differentiation through a let-7-independent mechanism. Indeed, we found that Lin28 proteins bind a highly conserved element in the 3' UTR of Hmga2 mRNA, and this provokes a down-regulation of its translation. This mechanism prevents the inappropriate accumulation of Hmga2 that would modify the proliferation and physiological apoptosis of differentiating ESCs. In summary, we demonstrated that during ESC differentiation, Lin28 transient induction is dependent on Otx2 and Hmga2 and prevents an inappropriate excessive rise of Hmga2 levels.-Parisi, S., Passaro, F., Russo, L., Musto, A., Navarra, A., Romano, S., Petrosino, G., Russo, T. Lin28 is induced in primed embryonic stem cells and regulates let-7-independent events.

Evidence of lower oxygen reserves during labour in the growth restricted human foetus: a retrospective study.

BACKGROUND: The aim of the present study is to test the hypothesis that Growth Restricted foetuses (FGR) have the tendency to develop more pathological cardiotocograpic tracings during labour than do appropriate for gestational age foetuses and that there is a shorter time lapse from the beginning of labour and the advent of a pathological cardiotocograpic tracing. METHODS: The study was carried out at the Maternal-Foetal Medicine Unit of the Sant'Anna University Hospital, Turin, Italy. A total of 930 foetuses born at term between January and December 2012 were analysed: 355 small for gestational age (SGA) comprising both constitutional small for gestational age and growth restricted foetuses (cases group) and 575 Appropriate for Gestational Age (AGA) foetuses (control group). Tracings were evaluated independently by two obstetric consultants, according to the International Federation of Gynaecology and Obstetrics (FIGO) classification. The main outcomes considered were the incidence of pathological cardiotocograpic tracings and the time interval between the beginning of labour and the advent of pathological cardiotocograpic tracing. The Student's t-test, chi-square test and ANOVA were used for comparisons between cases and controls and amongst groups. Significance was set at <0.05. Univariate and multivariate odds-ratios were calculated. RESULTS: Foetuses with birthweight <3rd centile (growth restricted foetuses) more frequently presented pathological cardiotocograpic tracings in labour than did controls (43.8% vs. 21.6%; p < 0.001). Pathological cardiotocograpic tracing developed faster in the foetuses with birthweight <3rd centile group (53', 0'-277') than it did in the control group (170.5', 0'-550'; p < 0.05). A higher induction rate was observed in the cases (29.6%) than in the control group (17%), with statistical significance p < 0.001. To correct for this possible confounding factor a multivariate logistic regression analysis was performed. It confirmed a statistically significant increased risk of pathological cardiotocographic tracings in the FGR group (OR 1.63; CI 1.30-2.05). CONCLUSION: The results confirm the hypothesis that Growth Restricted foetuses (FGR) have fewer oxygen reserves to deal with labour. Our results underscore the importance of the prenatal detection of these foetuses and of their continuous cardiotocographic monitoring during labour.

Hmga2 is necessary for Otx2-dependent exit of embryonic stem cells from the pluripotent ground state.

BACKGROUND: A crucial event in the differentiation of mouse embryonic stem cells (ESCs) is the exit from the pluripotent ground state that leads to the acquisition of the 'primed' pluripotent phenotype, characteristic of the epiblast-like stem cells (EpiLCs). The transcription factors Oct4 and Otx2 play a key role in this phenomenon. In particular, Otx2 pioneers and activates new enhancers, which are silent in ESCs and which control the transcription of genes responsible for the acquisition of the EpiLC phenotype. An important point that remains to be addressed is the mechanism through which Otx2 engages the new enhancers and stably associates with them. Hmga2 is a member of the high-mobility group family of proteins, non-histone components of chromatin whose expression is high during embryogenesis and becomes low or undetectable in adults. Its high expression during embryogenesis suggests that Hmga2 fulfills important roles in development. RESULTS: Here, we demonstrate that Hmga2 accumulates soon after the induction of ESC differentiation. Its suppression hampers the exit of ESCs from the pluripotent ground state and their differentiation into EpiLCs. Mechanistically, Hmga2 controls the differentiation process by cooperating with Otx2 in the pioneering of new enhancers. In Hmga2 null induced pluripotent stem cells we observe that Otx2 fails to regulate its target genes upon the induction of differentiation. Hmga2 associates to Otx2-bound loci in EpiLCs, and in Hmga2 KO cells Otx2 is unable to engage and activate the new enhancers, thus indicating that Hmga2 is required for the binding of Otx2 to its cis-elements. We find that this mechanism also operates on the Hmga2 gene, which is one of the targets of Otx2, thus indicating the existence of a positive feedback loop. CONCLUSIONS: Our findings reveal a novel mechanism necessary for the exit of ESCs from the pluripotent ground state. Upon the induction of ESC differentiation, Otx2 alone or in combination with Oct4 engages new enhancers, which are silent in undifferentiated ESCs. The Hmga2 gene is activated by Otx2 and Hmga2 protein binds to the enhancers targeted by Otx2, thus facilitating the engagement and/or the stable association of Otx2. Therefore, our results demonstrate that Hmga2 is a key element of the regulatory network that governs the exit of ESCs from the pluripotent ground state.

Pregnancy outcomes after kidney graft in Italy: are the changes over time the result of different therapies or of different policies? A nationwide survey (1978-2013).

BACKGROUND: Kidney transplantation is the treatment of choice to restore fertility to women on renal replacement therapy. Over time, immunosuppressive, support therapies and approaches towards high-risk pregnancies have changed. The aim of this study was to analyse maternal-foetal outcomes in two cohorts of transplanted women who delivered a live-born baby in Italy in 1978-2013, dichotomized into delivery before and after January 2000. METHODS: A survey involving all the Italian transplant centres was carried out, gathering data on all pregnancies recorded since the start of activity at each centre; the estimated nationwide coverage was 75%. Data on cause of ESRD, dialysis, living/cadaveric transplantation, drug therapy, comorbidity, and the main maternal-foetal outcomes were recorded and reviewed. Data were compared with a low-risk cohort of pregnancies from two large Italian centres (2000-14; Torino and Cagliari Observational Study cohort). RESULTS: The database consists of 222 pregnancies with live-born babies after transplantation (83 before 2000 and 139 in 2000-13; 68 and 121 with baseline and birth data, respectively), and 1418 low-risk controls. The age of the patients significantly increased over time (1978-99: age 30.7 ± 3.7 versus 34.1 ± 3.7 in 2000-13; P < 0.001). Azathioprine, steroids and cyclosporine A were the main drugs employed in the first time period, while tacrolimus emerged in the second. The prevalence of early preterm babies increased from 13.4% in the first to 27.1% in the second period (P = 0.049), while late-preterm babies non-significantly decreased (38.8 versus 33.1%), thus leaving the prevalence of all preterm babies almost unchanged (52.2 and 60.2%; P = 0.372). Babies below the 5th percentile decreased over time (22.2 versus 9.6%; P = 0.036). In spite of high prematurity rates, no neonatal deaths occurred after 2000. The results in kidney transplant patients are significantly different from controls both considering all cases [preterm delivery: 57.3 versus 6.3%; early preterm: 22.2 versus 0.9%; small for gestational age (SGA): 14 versus 4.5%; P < 0.001] and considering only transplant patients with normal kidney function [preterm delivery: 35 versus 6.3%; early preterm: 10 versus 0.9%; SGA: 23.7 versus 4.5% (P < 0.001); risks increase across CKD stages]. Kidney function remained stable in most of the patients up to 6 months after delivery. Multiple regression analysis performed on the transplant cohort highlights a higher risk of preterm delivery in later CKD stages, an increase in preterm delivery and a decrease in SGA across periods. CONCLUSIONS: Pregnancy after transplantation has a higher risk of adverse outcomes compared with the general population. Over time, the incidence of SGA babies decreased while the incidence of 'early preterm' babies increased. Although acknowledging the differences in therapy (cyclosporine versus tacrolimus) and in maternal age (significantly increased), the decrease in SGA and the increase in prematurity may be explained by an obstetric policy favouring earlier delivery against the risk of foetal growth restriction.

Hypertension in CKD Pregnancy: a Question of Cause and Effect (Cause or Effect? This Is the Question).

Chronic kidney disease (CKD) is increasingly encountered in pregnancy, and hypertension is frequently concomitant. In pregnancy, the prevalence of CKD is estimated to be about 3%, while the prevalence of chronic hypertension is about 5-8%. The prevalence of hypertension and CKD in pregnancy is unknown. Both are independently related to adverse pregnancy outcomes, and the clinical picture merges with pregnancy-induced hypertension and preeclampsia. Precise risk quantification is not available, but risks linked to CKD stage, hypertension, and proteinuria are probably multiplicative, each at least doubling the rates of preterm and early preterm delivery, small for gestational age babies, and related outcomes. Differential diagnosis (based upon utero-placental flows, fetal growth, and supported by serum biomarkers) is important for clinical management. In the absence of guidelines for hypertension in CKD pregnancies, the ideal blood pressure goal has not been established; we support a tailored approach, depending on compliance, baseline control, and CKD stages, with strict blood pressure monitoring. The choice of antihypertensive drugs and the use of diuretics and of erythropoiesis-stimulating agents (ESAs) are still open questions which only future studies may clarify.

Vegan-vegetarian low-protein supplemented diets in pregnant CKD patients: fifteen years of experience.

BACKGROUND: Pregnancy in women with advanced CKD becoming increasingly common. However, experience with low-protein diets in CKD patients in pregnancy is still limited. Aim of this study is to review the results obtained over the last 15 years with moderately restricted low-protein diets in pregnant CKD women (combining: CKD stages 3-5, proteinuria: nephrotic at any time, or > =1 g/24 at start or referral; nephrotic in previous pregnancy). CKD patients on unrestricted diets were employed for comparison. STUDY PERIOD: January, 2000 to September, 2015: 36 on-diet pregnancies (31 singleton deliveries, 3 twin deliveries, 1 pregnancy termination, 1 miscarriage); 47 controls (42 singleton deliveries, 5 miscarriages). The diet is basically vegan; since occasional milk and yoghurt are allowed, we defined it vegan-vegetarian; protein intake (0.6-0.8 g/Kg/day), keto-acid supplementation, protein-unrestricted meals (1-3/week) are prescribed according to CKD stage and nutritional status. Statistical analysis was performed as implemented on SPSS. RESULTS: Patients and controls were similar (p: ns) at baseline with regard to age (33 vs 33.5), referral week (7 vs 9), kidney function (CKD 3-5: 48.4 % vs 64.3 %); prevalence of hypertension (51.6 % vs 40.5 %) and proteinuria >3 g/24 h (16.1 % vs 12.2 %). There were more diabetic nephropathies in on-diet patients (on diet: 31.0 % vs controls 5.3 %; p 0.007 (Fisher)) while lupus nephropathies were non-significantly higher in controls (on diet: 10.3 % vs controls 23.7 %; p 0.28 (Fisher)). The incidence of preterm delivery was similar (<37 weeks: on-diet singletons 77.4 %; controls: 71.4 %). The incidence of other adverse pregnancy related outcomes was non-significantly lower in on-diet patients (early preterm delivery: on diet: 32.3 % vs controls 35.7 %; birth-weight = <1.500 g: on diet: 9.7 % vs controls 23.8 %). None of the singletons in the on-diet series died, while two perinatal deaths occurred among the controls (p = 0.505). The incidence of small for gestational age (SGA <10th centile) and/or extremely preterm babies (<28th week) was significantly lower in singletons from on-diet mothers than in controls (on diet: 12.9 % vs controls: 33.3 %; p: 0.04 (Fisher)). CONCLUSION: Moderate protein restriction in the context of a vegan-vegetarian supplemented diet is confirmed as a safe option in the management of pregnant CKD patients.

Angiotensin receptor I stimulates osteoprogenitor proliferation through TGFß-mediated signaling.

Clinical studies of large human populations and pharmacological interventions in rodent models have recently suggested that anti-hypertensive drugs that target angiotensin II (Ang II) activity may also reduce loss of bone mineral density. Here, we identified in a genetic screening the Ang II type I receptor (AT1R) as a potential determinant of osteogenic differentiation and, implicitly, bone formation. Silencing of AT1R expression by RNA interference severely impaired the maturation of a multipotent mesenchymal cell line (W20-17) along the osteoblastic lineage. The same effect was also observed after the addition of the AT1R antagonist losartan but not the AT2R inhibitor PD123,319. Additional cell culture assays traced the time of greatest losartan action to the early stages of W20-17 differentiation, namely during cell proliferation. Indeed, addition of Ang II increased proliferation of differentiating W20-17 and primary mesenchymal stem cells and this stimulation was reversed by losartan treatment. Cells treated with losartan also displayed an appreciable decrease of activated (phosphorylated)-Smad2/3 proteins. Moreover, Ang II treatment elevated endogenous transforming growth factor ß (TGFß) expression considerably and in an AT1R-dependent manner. Finally, exogenous TGFß was able to restore high proliferative activity to W20-17 cells that were treated with both Ang II and losartan. Collectively, these results suggest a novel mechanism of Ang II action in bone metabolism that is mediated by TGFß and targets proliferation of osteoblast progenitors.

Is renal hyperfiltration protective in chronic kidney disease-stage 1 pregnancies? A step forward unravelling the mystery of the effect of stage 1 chronic kidney disease on pregnancy outcomes.

BACKGROUND: The correlation between advanced or proteinuric chronic kidney disease (CKD) and adverse pregnancy outcomes is intuitive, although how early CKD affects pregnancy remains unknown. Glomerular hyperfiltration is a physiological response to pregnancy, correlated with outcomes in hypertension or collagen diseases. The aim of the study was to correlate first trimester hyperfiltration with pregnancy outcomes in stage 1 CKD patients. METHODS: A historical prospective study was conducted on the database of our Unit, gathering all pregnant CKD patients referred since 1 January 2000. From 383 pregnancies referred in 2000-2013, 75 patients were selected (stage 1 CKD, referred within the 14th gestational week, singleton deliveries, absence of diabetes, hypertension or nephrotic proteinuria at referral, body mass index [BMI] < 30); 267 'low-risk' pregnancies, followed in the same setting, served as controls. Glomerular filtration rate (GFR) was assessed by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and dichotomized at 120 mL/min. The odds for Caesarean section, prematurity, need for Neonatal Intensive Care Unit (NICU) were assessed by univariate analysis and logistic regression. RESULTS: Risk for adverse pregnancy outcomes was not affected by hyperfiltration (univariate OR GFR ≥ 120 mL/min: Caesarean section 1.30 (0.46-3.65); preterm delivery: 0.84 (0.25-2.80)). In contrast, even in these cases with normal kidney function, stage 1 CKD was associated with prematurity (17.3% vs 4.9% P = 0.001), lower birth weight (3027 ± 586 versus 3268 ± 500 P < 0.001) need for NICU (12% vs 1.1% P < 0.001). In the multivariate analysis, the risks were significantly increased by proteinuria and maternal age but not by GFR. CONCLUSIONS: In pregnant Stage 1 CKD patients, hyperfiltration was not associated with maternal-foetal outcomes, thus suggesting a need to focus attention on qualitative factors, eventually enhanced by age, as vascular stiffness, endothelial damage or oxidative stress.

Chronic kidney disease may be differentially diagnosed from preeclampsia by serum biomarkers.

Preeclampsia, affecting 5-8% of pregnancies, is the main cause of fetal-maternal mortality and morbidity. The differential diagnosis with chronic kidney disease (CKD) is a challenge owing to the overlapping clinical features. No biomarker has been found to discriminate between the two conditions. Here, we tested whether maternal serum levels of placental growth factor (PlGF) and soluble FMS-like tyrosine kinase-1 (sFlt-1), markers of preeclampsia, could be used to discriminate between 34 patients with preeclampsia, 23 patients with CKD during pregnancy, and 38 healthy pregnant women. Serum levels of PlGF and sFlt-1 were determined during the third trimester by commercially available immunoassays. In preeclampsia, sFlt-1 levels were significantly increased in comparison with that in CKD and in the control women. Serum levels of PlGF in preeclampsia were significantly decreased relative to both controls and patients with CKD. The sFlt-1 to PlGF ratio was significantly increased in preeclampsia (median 436) compared with controls (median 9.4) and CKD (median 4.0). No differences were found between controls and patients with CKD. Thus, our study suggests that it is possible to discriminate between preeclampsia and CKD during pregnancy by determining maternal serum levels of sFlt-1 and PlGF and their ratio.