Fetopathy associated with exposure to angiotensin converting enzyme inhibitors and angiotensin receptor antagonists

Neonatal Renal Failure Following Intrauterine Exposure to an Angiotensin-Converting Enzyme Inhibitor

The renin-angiotensin-aldosterone system (RAAS) plays a crucial role in the normal development of the fetal kidney. Late pregnancy blockage of the RAAS, through in-utero exposure to angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers, is associated with poor fetal outcomes, including oligohydramnios, renal tubular dysplasia, postnatal anuric renal failure, and hypotension. The present case describes a 39-year-old primigravida that was referred to the emergency department, at 37 weeks, for the evaluation of intrauterine growth restriction and suspected coarctation of the aorta (CoA). She was medicated with enalapril since the 35th week of gestation. She delivered a male infant, weighing 2,110 g, with no apparent malformations. CoA was excluded. During his first day of life, the patient developed anuria, acute renal failure, and hypotension, requiring ionotropic support. Renal ultrasound appeared normal. Diuresis was reinitiated at 48 hours of life after continued supportive measures. Kidney function tests progressively normalized. Additional investigations revealed a low concentration of angiotensin-converting enzyme. The patient is currently 12 months old and has had a favorable evolution. This case highlights the fact that even brief exposure to enalapril in the third trimester may cause RAAS blocker fetopathy. As long-term sequelae of ACEI-exposed infants are poorly described, close follow-up of renal complications is essential. Physicians should be aware of the deleterious effects of RAAS blockers in pregnancy.

The role of immune cells and mediators in preeclampsia

Preeclampsia is a hypertensive disorder of major concern in pregnancy than can lead to intrauterine growth restriction, placental abruption and stillbirth. The pathophysiology of preeclampsia is multifactorial, including not only kidney dysfunction but also endothelial dysfunction, as the maternal endothelium becomes exposed to placental factors that are released into the circulation and increase systemic levels of vasoconstrictors, oxidative stress, anti-angiogenic factors and inflammatory mediators. Importantly, inflammation can lead to insufficient placental perfusion and low birthweight in offspring. Various innate and adaptive immune cells and mediators have been implicated in the development of preeclampsia, in which oxidative stress is associated with activation of the maternal inflammatory response. Immune cells such as regulatory T cells, macrophages, natural killer cells, and neutrophils are known to have major causative roles in the pathology of preeclampsia, but the contributions of additional immune cells such as B cells, inflammatory cytokines and anti-angiotensin II type 1 receptor autoantibodies are also now recognized. Immunological interventions, therefore, have therapeutic potential in this disease. Here, we provide an overview of the immune responses that are involved in the pathogenesis of preeclampsia, including the role of innate and adaptive immune cells and mediators.

Structural, spectroscopic, molecular docking, ADME, molecular dynamics studies of Val-Trp dipeptide

Hypertension is a significant risk factor for various diseases, especially heart, brain, and kidney diseases. It is known that many peptides have the property of lowering blood pressure and determine as ACE inhibitors. The purpose of this study is to obtain information about the molecular structure of Val-Trp (L-valyl-L-tryptophan), which is one of the antihypertensive peptides, by molecular mechanical, quantum mechanical, and spectroscopic methods (FT-IR and Raman). Also, it is aimed to investigate the interactions of Val-Trp dipeptide with receptors related to hypertension and to determine the pharmacokinetic profile due to the potential of the peptide to be a drug candidate. The peptide structure was optimized by DFT/B3LYP/6-311++G(d,p) basis set, then vibrational wavenumbers, molecular electrostatic potential (MEP), HOMO-LUMO (highest occupied molecular orbital- lowest unoccupied molecular orbital), NBO (natural bond orbital) analyzes were performed. The assignment of fundamental theoretical vibration wavenumbers was carried out with potential energy distribution analysis (PED). After the structural analyzes of the peptide were performed, the interactions of the peptide with Angiotensin-converting enzyme (ACE), Angiotensin II Receptor Type 1 (AT1R) and Renin were investigated by molecular docking study. Then, the molecular dynamic (MD) simulation of the peptide-ACE complex with the best binding affinity in the molecular docking studies was carried out for 50 ns. ADME (absorption, distribution, metabolism, and excretion) analysis of Val-Trp dipeptide was performed. In support of the studies carried out, enlightening information about the feasibility of the antihypertensive drug of Val-Trp dipeptide with the help of the ADME profile was presented to the literature.Communicated by Ramaswamy H. Sarma.

Inhibition of the AT1R agonistic autoantibody in a rat model of preeclampsia improves fetal growth in late gestation

Placenta ischemia, the initiating event in preeclampsia (PE), is associated with fetal growth restriction. Inhibition of the agonistic autoantibody against the angiotensin type 1 receptor AT1-AA, using an epitope-binding inhibitory peptide ('n7AAc') attenuates increased blood pressure at gestational day (G)19 in the clinically relevant reduced uterine perfusion pressure (RUPP) model of PE. Thus we tested the hypothesis that maternal administration of 'n7AAc' does not transfer to the fetus, improves uterine blood flow and fetal growth, and attenuates elevated placental expression of miRNAs implicated in PE and FGR. Sham or RUPP surgery was performed at G14 with vehicle or 'n7AAc' (144 µg/day) administered via an osmotic pump from G14 to G20. Maternal plasma levels of the peptide on G20 were 16.28 ± 4.4 nM, and fetal plasma levels were significantly lower at 1.15 ± 1.7 nM (P = 0.0007). The uterine artery resistance index was significantly elevated in RUPP (P < 0.0001) but was not increased in 'n7AAc'-RUPP or 'n7AAc'-Sham versus Sham. A significant reduction in fetal weight at G20 in RUPP (P = 0.003) was not observed in 'n7AAc'-RUPP. Yet, percent survival was reduced in RUPP (P = 0.0007) and 'n7AAc'-RUPP (P < 0.0002). Correlation analysis indicated the reduction in percent survival during gestation was specific to the RUPP (r = 0.5342, P = 0.043) and independent of 'n7AAc'. Placental miR-155 (P = 0.0091) and miR-181a (P = 0.0384) expression was upregulated in RUPP at G20 but was not elevated in 'n7AAc'-RUPP. Collectively, our results suggest that maternal administration of 'n7AAc' does not alter fetal growth in the RUPP implicating its potential as a therapeutic for the treatment of PE.NEW & NOTEWORTHY The seven amino acid inhibitory peptide to the AT1-AA ('n7AAc') has limited transfer to the fetus at gestational day 20, improves uterine blood flow and fetal growth in the reduced uterine perfusion pressure model of preeclampsia (PE), and does not impair fetal survival during gestation in sham-operated or placental ischemic rats. Collectively, these findings suggest that maternal administration of 'n7AAc' as an effective strategy for the treatment of PE is associated with improved outcomes in the fetus.

Reshaping the Preterm Heart: Shifting Cardiac Renin-Angiotensin System Towards Cardioprotection in Rats Exposed to Neonatal High-Oxygen Stress

BACKGROUND

Approximately 10% of infants are born preterm. Preterm birth leads to short and long-term changes in cardiac shape and function. By using a rat model of neonatal high-oxygen (80%O₂) exposure, mimicking the premature hyperoxic transition to the extrauterine environment, we revealed a major role of the renin-angiotensin system peptide Angio II (angiotensin II) and its receptor AT1 (angiotensin receptor type 1) on neonatal O₂-induced cardiomyopathy. Here, we tested whether treatment with either orally active compounds of the peptides Angio-(1-7) or alamandine included in cyclodextrin could prevent postnatal cardiac remodeling and the programming of cardiomyopathy induced by neonatal high-O₂ exposure.

METHODS

Sprague-Dawley pups were exposed to room air or 80% O₂ from postnatal day 3 (P3) to P10. Neonatal rats were treated orally from P3 to P10 and assessed at P10 and P28. Left ventricular (LV) shapes were characterized by tridimensional computational atlases of ultrasound images in addition to histomorphometry.

RESULTS

At P10, high O₂-exposed rats presented a smaller, globular and hypertrophied LV shape versus controls. Treatment with cyclodextrin-Angio-(1-7) significantly improved LV function in the O₂-exposed neonatal rats and slightly changed LV shape. Cyclodextrin-alamandine and cyclodextrin-Angio-(1-7) treatments similarly reduced hypertrophy at P10 as well as LV remodeling and dysfunction at P28. Both treatments upregulated cardiac angiotensin-converting enzyme 2 in O₂-exposed rats at P10 and P28.

CONCLUSIONS

Our findings demonstrate LV remodeling changes induced by O₂-stress and the potential benefits of treatments targeting the cardioprotective renin-angiotensin system axis, supporting the neonatal period as an important window for interventions aiming at preventing cardiomyopathy in people born preterm.

Increased risk of major congenital malformations in early pregnancy use of angiotensin-converting-enzyme inhibitors and angiotensin-receptor-blockers: a meta-analysis

AIMS

To evaluate the risk of adverse fetal outcomes after exposure to angiotensin converting enzyme inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs) in first trimester of pregnancy, by conducting a systematic review and meta-analysis.

MATERIALS AND METHODS

A systematic literature search was conducted using Medline, Embase, Cochrane and PubMed from inception to 25 November 2019. Studies were included if they evaluated pregnancies exposed to ACE-Is or ARBs, reported fetal outcomes, and compared these outcomes with a control group. Pooled odds ratios (ORs) were estimated using inverse variance-weighted random effects model. The protocol was registered with the PROSPERO International Prospective Register of Systematic Reviews (CRD42020160566).

RESULTS

Studies reporting on 6234 pregnancies exposed to ACE-Is or ARBs, 4104 pregnancies exposed to other oral antihypertensives, and 1,872,733 pregnancies without exposure were included in the meta-analysis. ACE-I or ARB exposed pregnancies, compared to non-exposed controls, had higher risk of major congenital malformations (OR 1.82; 95% confidence interval [CI]: 1.42-2.34), cardiovascular malformations (OR 2.50; 95% CI: 1.62-3.87) and stillbirths (OR 1.75; 95% CI: 1.21-2.53). There was no difference in congenital malformations observed between pregnancies exposed to other antihypertensives compared to non-exposed controls (OR 0.96; 95% CI: 0.69-1.33).

CONCLUSIONS

Women exposed to ACE-Is or ARBs during early pregnancy had higher risk of adverse fetal outcomes, including malformations and stillbirths, than non-exposed controls. This increased risk was independent of underlying maternal hypertension, as those exposed to other antihypertensives did not exhibit a higher risk than healthy controls. Women planning for pregnancy using these medications, including those with diabetic nephropathy, should be counselled appropriately.

The First Thousand Days: Kidney Health and Beyond

The global burden of chronic kidney disease (CKD) is rising. A superior strategy to advance global kidney health is required to prevent and treat CKD early. Kidney development can be impacted during the first 1000 days of life by numerous factors, including malnutrition, maternal illness, exposure to chemicals, substance abuse, medication use, infection, and exogenous stress. In the current review, we summarize environmental risk factors reported thus far in clinical and experimental studies relating to the programming of kidney disease, and systematize the knowledge on common mechanisms underlying renal programming. The aim of this review is to discuss the primary and secondary prevention actions for enhancing kidney health from pregnancy to age 2. The final task is to address the potential interventions to target renal programming through updating animal studies. Together, we can enhance the future of global kidney health in the first 1000 days of life.

Pathological AT1R-B2R Protein Aggregation and Preeclampsia

Preeclampsia is one of the most frequent and severe complications of pregnancy. Symptoms of preeclampsia usually occur after 20 weeks of pregnancy and include hypertension and kidney dysfunction with proteinuria. Up to now, delivery of the infant has been the most effective and life-saving treatment to alleviate symptoms of preeclampsia because a causative treatment does not exist, which could prolong a pregnancy complicated with preeclampsia. Preeclampsia is a complex medical condition, which is attributed to a variety of different risk factors and causes. Risk factors account for insufficient placentation and impaired vasculogenesis and finally culminate in this life-threatening condition of pregnancy. Despite progress, many pathomechanisms and causes of preeclampsia are still incompletely understood. In recent years, it was found that excessive protein complex formation between G-protein-coupled receptors is a common sign of preeclampsia. Specifically, the aberrant heteromerization of two vasoactive G-protein-coupled receptors (GPCRs), the angiotensin II AT1 receptor and the bradykinin B2 receptor, is a causative factor of preeclampsia symptoms. Based on this knowledge, inhibition of abnormal GPCR protein complex formation is an experimental treatment approach of preeclampsia. This review summarizes the impact of pathological GPCR protein aggregation on symptoms of preeclampsia and delineates potential new therapeutic targets.

Available medications used as potential therapeutics for COVID-19: What are the known safety profiles in pregnancy

BACKGROUND

Medications already available to treat other conditions are presently being studied in clinical trials as potential treatments for COVID-19. Given that pregnant women are excluded from these trials, we aimed to investigate their safety when used during pregnancy within a unique population source.

METHODS

Using the population-based Quebec Pregnancy Cohort, we identified women who delivered a singleton liveborn (1998-2015). Taking potential confounders into account including indications for use, the risk of prematurity, low birth weight (LBW), small for gestational age (SGA), and major congenital malformation (MCM) associated with COVID-19 repurposed drug use during pregnancy were quantified using generalized estimation equations.

RESULTS

Of the 231,075 eligible pregnancies, 107 were exposed to dexamethasone (0.05%), 31 to interferons (0.01%), 1,398 to heparins (0.60%), 24 to angiotensin-receptor blockers (ARB) (0.01%), 182 to chloroquine (0.08%), 103 to hydroxychloroquine (0.05%), 6,206 to azithromycin (2.70%), 230 to oseltamivir (0.10%), and 114 to HIV medications (0.05%). Adjusting for potential confounders, we observed an increased risk of prematurity related to dexamethasone (aOR 1.92, 95%CI 1.11-3.33; 15 exposed cases), anti-thrombotics (aOR 1.58, 95%CI 1.31-1.91; 177 exposed cases), and HIV medications (aOR 2.04, 95%CI 1.01-4.11; 20 exposed cases) use. An increased risk for LBW associated with anti-thrombotics (aOR 1.72, 95%CI 1.41-2.11; 152 exposed cases), and HIV medications (aOR 2.48, 95%CI 1.25-4.90; 21 exposed cases) use were also found. Gestational exposure to anti-thrombotics (aOR 1.20, 95%CI 1.00-1.44; 176 exposed cases), and HIV medications (aOR 2.61, 95%CI 1.51-4.51; 30 exposed cases) were associated with SGA. First-trimester dexamethasone (aOR 1.66, 95%CI 1.02-2.69; 20 exposed cases) and azithromycin (aOR 1.10, 95%CI 1.02-1.19; 747 exposed cases) exposures were associated with MCM.

CONCLUSIONS

Many available medications considered as treatments for COVID-19 are associated with adverse pregnancy outcomes. Caution is warranted when considering these medications during the gestational period.

Valsartan exposure in pregnancy with resultant anhydramnios and chronic kidney disease in a late preterm infant

In utero exposure to angiotensin II receptor blockers (ARBs) has fetotoxic effects including renal failure, oligohydramnios and lung hypoplasia. We present the case of a 24-year-old woman who presented to the maternity services in the 34th week of her first pregnancy. She was taking valsartan for hypertension. Ultrasound showed a structurally normal fetus with anhydramnios. The patient was admitted and valsartan was discontinued. She had spontaneous preterm delivery at 35 weeks' gestation of a baby girl. The baby's urine output was minimal in the first week of life and she was transferred to a paediatric hospital for specialist nephrology input. At 6 months of age, she requires ongoing nephrology follow-up and she remains on treatment for hypertension and anaemia. This case demonstrates the serious adverse effects resulting from ARB exposure in utero, and highlights the importance of avoiding fetotoxic medications in women of childbearing age.

Can patterns of medication use explain the increasing incidence of end stage kidney disease among people with diabetes in Australia?

AIMS

Recently, an increase in the incidence of end-stage kidney disease (ESKD) among people with type 2 diabetes (T2D) aged < 50 years and ≥ 80 years has been observed in Australia. We examined whether patterns of medication use are likely to explain these trends.

METHODS

Among National Diabetes Services Scheme registrants, we determined the annual prevalence of dispensed glucose-lowering (GL), blood-pressure-lowering (BPL) and lipid-lowering (LL) agents with ≥3, ≥6 or ≥9 dispensings per year from 2003 to 2013. Relative changes in the prevalence were determined via Poisson regression.

RESULTS

During 2003-2013, the percentage of people with T2D dispensed GL, BPL and LL agents with ≥3, ≥6 or ≥9 dispensings per year increased in all age-groups. From 2003 to 2013, GL, BPL and LL agents use with ≥3 dispensings per year increased by 17%, 8.2%, and 53%, respectively. The use of renin-angiotensin-aldosterone-system-blockers over time also increased but more slowly in those aged <60 years compared to those aged ≥80 years (6% vs 18%, p < 0.001).

CONCLUSIONS

Changes in medication use are not likely to explain increasing incidence of ESKD in younger Australians with T2D. Studies are needed to provide insights into the major drivers of the rising incidence of ESKD in this population.

Managing migraine in pregnancy and breastfeeding

The disproportionate prevalence of migraine among women in their reproductive years underscores the clinical significance of migraine during pregnancy. This paper discusses how migraine evolves during pregnancy, secondary headache disorders presenting in pregnancy and puerperium, and acute and preventive options for migraine management during pregnancy and lactation. Migraine is influenced by rising estrogen levels during pregnancy and their sharp decline in puerperium. Migraine, and migraine aura, can present for the first time during pregnancy and puerperium. There is also a higher risk for the development of preeclampsia and cerebrovascular headache during these periods. New or refractory headache, hypertension, and abnormal neurological signs are important "red flags" to consider. This paper reviews the diagnostic utility of neuroimaging studies and the risks of each during pregnancy. Untreated migraine can itself lead to preterm delivery, preeclampsia, and low birth weight infants. Behavioral interventions and lifestyle modifications are the cornerstone for migraine treatment during pregnancy. In addition, one should consider the risks and efficacy of each treatment during pregnancy on an individual basis. The protective nature of breastfeeding for migraine is debated, but there is no evidence to suggest breastfeeding worsens migraine. Acute and preventive migraine treatment options are available for nursing mothers. Neuromodulation and neurostimulation devices are additional options for treatment during pregnancy and lactation, while the safety of using calcitonin gene-related peptide receptor antagonists during these times remains to be determined.

Pregnancy after Heart Transplantation

As post-transplant survival improves, many heart transplant (HT) recipients are of, or are surviving to, childbearing age. Solid-organ transplant recipients who become pregnant should be managed by a multidisciplinary cardio-obstetrics team, including specialists in maternal and fetal medicine, cardiology and transplant medicine, as well as anesthesia, neonatology, psychology, genetics, and social services. With careful patient selection, pregnancy after HT can been managed safely. The purpose of this comprehensive review was to summarize the current evidence and recommendations surrounding preconception counseling, medical management and surveillance, maternal outcomes, breastfeeding, and remaining gaps in knowledge.

Pharmacotherapy for hypertension in pregnant patients: special considerations

INTRODUCTION

Hypertensive disorders of pregnancy (HDP) represent a major cause of maternal, fetal and neonatal morbidity and mortality and identifies women at risk for cardiovascular and other chronic diseases later in life. When antihypertensive drugs are used during pregnancy, their benefit and harm to both mother and fetus should be evaluated.

AREAS COVERED

This review summarizes the pharmacological characteristics of the recommended antihypertensive drugs and their impact on mother and fetus when administered during pregnancy and/or post-partum. Drugs were identified using MEDLINE and the main international Guidelines for the management of HDP.

EXPERT OPINION

Although there is a consensus that severe hypertension should be treated, treatment of mild hypertension without end-organ damage (140-159/90-109 mmHg) remains controversial and there is no agreement on when to initiate therapy, blood pressure targets or recommended drugs in the absence of robust evidence for the superiority of one drug over others. Furthermore, the long-term outcomes of in-utero antihypertensive exposure remain uncertain. Therefore, evidence-based data regarding the treatment of HDP is lacking and well designed randomized clinical trials are needed to resolve all these controversial issues related to the management of HDP.

Prenatal hypocalvaria after prolonged intrauterine exposure to angiotensin II receptor antagonists

We report a case of prenatal exposure to angiotensin II receptor antagonists (ARA II) from the beginning of pregnancy in a patient with a hypokinetic dilated cardiomyopathy. This case report emphasizes the fetal renal impact of prolonged intrauterine exposure to renin-angiotensin system (RAS) blockers, and highlights that this exposure can cause severe prenatal hypocalvaria. This delayed ossification can be reversible after birth, but the presence of anhydramnios indicates an early and irreversible block of RAS blockers in the fetus that is responsible for fetal kidney development abnormalities. This association carries a high risk of neonatal death. Prolonged exposure to ARA II or other RAS blockers remains prohibited throughout pregnancy.

Unique Populations with Episodic Migraine: Pregnant and Lactating Women

PURPOSE OF REVIEW

Migraine is a disabling and prevalent neurological disease, commonly affecting women during their reproductive years. It is crucial for providers to be able to adequately counsel women who are pregnant, planning pregnancy, or nursing, regarding preventive and abortive treatment options for episodic migraine. This review will discuss (1) the expected course of migraine during pregnancy and the post-partum period, (2) recommended preventive therapies for migraine during pregnancy and lactation, and (3) recommended abortive medications for migraine during pregnancy and lactation.

RECENT FINDINGS

Recent research has indicated safety for triptan use during pregnancy and ibuprofen use during the first trimester of pregnancy. Considerations for use of emerging migraine-preventive treatment, such as non-invasive neurostimulators, are discussed. For clinical decision-making and patient counseling, it is important to understand both the limitations in determining teratogenic effects in humans and the principles affecting medication transmission from mother to breast milk.

Flavonoid-Rich Extract of Actinidia macrosperma (A Wild Kiwifruit) Inhibits Angiotensin-Converting Enzyme In Vitro

Increasing interest in flavonoids in kiwifruit is due to the health-promoting properties of these bioactives. Inhibition of the angiotensin-converting enzyme (ACE) is one of the main therapeutic targets in controlling hypertension. The present study investigated the ACE inhibitory activity of flavonoid-rich extracts obtained from different kiwifruit genotypes. The flavonoid-rich extracts were prepared from fruits of Actinidia macrosperma, Actinidia deliciosa cv Hayward (Green kiwifruit), and Actinidia chinensis cv Hort 16A (Gold kiwifruit) by steeping the lyophilized fruit samples in 70% aqueous acetone, followed by partitioning the crude extracts with hexane. The composition of each extract was analyzed using ultrahigh-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). The ACE inhibitory activity of the fruit extracts was performed using a fluorescence-based biochemical assay. The subclass flavonol was the most abundant group of flavonoids detected in all the extracts tested from three different kiwifruit cultivars. Quercetin-3-O-galactoside, quercetin-3-O-glucoside, quercetin-3-O-rhamnoside, quercetin-3-O-rutinoside, quercetin-3-O-arabinoglucoside, catechin, epigallocatechin gallate, epigallocatechin, chlorogenic, ferulic, isoferulic, and caffeic acid were prominent phenolics found in A. macrosperma kiwifruit. Overall, the flavonoid-rich extract from A. macrosperma showed a significantly (p < 0.05) high percentage of inhibition (IC₅₀ = 0.49 mg/mL), and enzyme kinetic studies suggested that it inhibits ACE activity in vitro. The kiwifruit extracts tested were found to be moderately effective as ACE inhibitors in vitro when compared to the other plant extracts reported in the literature. Further studies should be carried out to identify the active compounds from A. macrosperma and to validate the findings using experimental animal models of hypertension.

Long-Lasting Androgen-Induced Cardiometabolic Effects in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, is characterized by androgen excess and ovarian dysfunction and presents with increased cardiometabolic risk factors such as obesity, insulin resistance, and elevated blood pressure (BP). We previously reported that administration of dihydrotestosterone (DHT) to female rats elicits cardiometabolic derangements similar to those found in women with PCOS. In this study, we tested the hypothesis that the DHT-mediated cardiometabolic derangements observed in PCOS are long lasting despite DHT withdrawal. Four-week-old female Sprague Dawley rats were treated with DHT (7.5 mg/90 days) or placebo for 6 months. DHT was discontinued (ex-DHT), and rats were followed for 6 additional months. After 6 months of DHT withdrawal, food intake, body weight, fat and lean mass, fasting plasma insulin, leptin, and adiponectin were elevated in ex-DHT rats. BP remained significantly elevated, and enalapril, an angiotensin-converting enzyme (ACE) inhibitor, normalized BP in ex-DHT rats. Expression of components of the intrarenal renin-angiotensin system was increased in ex-DHT rats. The cardiometabolic features found in ex-DHT rats were associated with lower plasma androgen levels but increased expression of renal and adipose tissue androgen receptors. In summary, androgen-induced cardiometabolic effects persisted after DHT withdrawal in a PCOS experimental model. Activation of intrarenal renin-angiotensin system plays a major role in the androgen-mediated increase in BP in ex-DHT. Upregulation of the renal and adipose tissue androgen receptor may explain the long-lasting effects of androgens. In clinical scenarios characterized by hyperandrogenemia in women, prompt normalization of androgen levels may be necessary to prevent their long-lasting cardiometabolic effects.

Long-Term Consequences of Fetal Angiotensin II Receptor Antagonist Exposure

Fetal angiotensin II receptor antagonist exposure is associated with major complications and even death when administered during pregnancy. Neonates frequently require intensive care treatment, and mortality is high. Despite this well-known risk potential, a considerable number of women still receive angiotensin II receptor antagonists during pregnancy to treat arterial hypertension. Although clinical symptoms in the neonatal period are well described, few reports address long-term follow-up after fetal exposure to angiotensin II receptor antagonists. We here report on a patient who was unwittingly exposed to olmesartan medoxomil during pregnancy. After birth, the neonate presented with mild clinical symptoms, mainly affecting the kidneys. However, neurodevelopmental follow-up revealed a delay in motor development with muscular hypotonia and failure to thrive at age 2 years. This case highlights the fact that, despite not causing neurological symptoms in the neonatal period, fetal angiotensin II receptor antagonist exposure during pregnancy might lead to neurodevelopmental impairment in later life.

Salvianolic acid B and danshensu induce osteogenic differentiation of rat bone marrow stromal stem cells by upregulating the nitric oxide pathway

The aim of the present study was to investigate the effect of salvianolic acid B (Sal B) and danshensu (DSU) on the osteogenic differentiation of bone marrow mesenchymal stem cells (MSCs) and the mechanisms of the effects. The osteogenic differentiation of MSCs in culture was assessed by measuring alkaline phosphatase (ALP) activity, osteocalcin (OCN) production, nitric oxide (NO) production and the mRNA expression levels of osteoprotegerin (OPG) and its ligand by MSCs. MSCs were successfully induced to differentiate into osteoblasts and adipocytes. Sal B and DSU increased the ALP activity and the production of OCN in the absence of an ossification inducer. The increase in ALP activity was more pronounced when induction was combined with the osteogenic inducer, Sal B, which enhanced the expression of OPG; however, Sal B reduced the expression of receptor activator of nuclear factor-κB ligand (RANKL) by MSCs. Sal B reversed the inhibitory effect of N-nitro L-arginine methylester on the MSCs and increased ALP activity, OCN content and the OPG/RANKL ratio. Based on these results, it was concluded that Sal B increases the osteogenic differentiation of MSCs, most likely by regulating the nitric oxide pathway.

Prescription drug use during pregnancy in France: a study from the national health insurance permanent sample

PURPOSE

To provide an up-to-date account of drug prescription during pregnancy in France from 2011 to 2014 using the permanent sample of the French national computerized healthcare database and with a focus on recommended supplementations, fetotoxic drugs and teratogenic drugs.

METHODS

All pregnancies identified by the International Classification of Diseases, 10th Revision codes list in the hospitalization database, lasting more than 9 weeks of amenorrhea and whose delivery occurred between 01/01/2011 and 12/31/2014, were included. Drugs delivered between the trimester before and until the end of the pregnancy were included. Drug exposure prevalence was calculated for each year and according to pregnancy trimesters.

RESULTS

The study included 28,491 pregnancies with a median number of 9 [5-13] (median [IQ range]) drugs delivered. The most prescribed drug class was antianemia (in 72.5% of exposed). The prescription rate of recommended vitamins (B9 and D) increased over the study period (+10%). Influenza vaccination also increased but remained at a low rate (1%). Exposure to fetotoxic drugs decreased as pregnancy advanced. Exposure to the main teratogenic antiepileptics was stable over the study period. Low-income pregnant women had a higher average drug consumption except for recommended vitamins.

CONCLUSION

Pregnant French women are among the largest consumers of prescription medications worldwide. Overall, the dispensation trends observed in this study are in line with the recommendations of the French National College of Gynecologists and Obstetricians. Nevertheless, while being low, exposure to fetotoxic drugs, teratogenic drugs or those under safety alerts still occurred. Supplementations and vaccines in low-income pregnant women should also be increased.

Potential functional and pathological side effects related to off-target pharmacological activity

Most pharmaceutical companies test their discovery-stage proprietary molecules in a battery of in vitro pharmacology assays to try to determine off-target interactions. During all phases of drug discovery and development, various questions arise regarding potential side effects associated with such off-target pharmacological activity. Here we present a scientific literature curation effort undertaken to determine and summarize the most likely functional and pathological outcomes associated with interactions at 70 receptors, enzymes, ion channels and transporters with established links to adverse effects. To that end, the scientific literature was reviewed using an on-line database, and the most commonly reported effects were summarized in tabular format. The resultant table should serve as a practical guide for research scientists and clinical investigators for the prediction and interpretation of adverse side effects associated with molecules interacting with components of this screening battery.

Placental transfer and mammary excretion of a novel angiotensin receptor blocker fimasartan in rats

Background

Fimasartan (FMS) is a potent angiotensin receptor blocker for the treatment of mild to moderate hypertension. This study aimed to evaluate the transfer of FMS to fetus and breast milk in rats.

Methods

In order to study the transfer to the fetus and nursing pup, pregnant and nursing maternal rats were administered with FMS by a constant intravenous infusion to reach target plasma concentrations of 200 ng/mL and 100 ng/mL. The concentrations of FMS in plasma, placenta, amniotic fluid, fetus, and milk were determined by a validated LC-MS/MS assay.

Results

Upon constant intravenous infusion, the plasma FMS concentration reached the target steady state concentrations (C_ss = 200 ng/mL and 100 ng/mL) in 24 h. The tissue-to-plasma partition coefficients (K_p) for placenta, amniotic fluid, and milk were obtained based on the observed FMS concentrations in the tissues and C_ss. The K_p values for all tissues were not different between high (C_ss = 200 ng/mL) and low (C_ss = 100 ng/mL) dose groups. While the mean K_p of the placenta was 44.6–59.0 %, the mean K_p was 1.3–1.7 % for the amniotic fluid and 14.9–17.0 % for fetus. The mean K_p of milk was 10.4–15.2 %.

Conclusions

Placental transfer and milk excretion of FMS was relatively lower compared to other angiotensin receptor blockers.

Activation of the Cardiac Renin-Angiotensin System in High Oxygen-Exposed Newborn Rats: Angiotensin Receptor Blockade Prevents the Developmental Programming of Cardiac Dysfunction

Newborn rats exposed to high oxygen (O2), mimicking preterm birth-related neonatal stress, develop later in life cardiac hypertrophy, dysfunction, fibrosis, and activation of the renin-angiotensin system. Cardiac renin-angiotensin system activation in O2-exposed adult rats is characterized by an imbalance in angiotensin (Ang) receptors type 1/2 (AT1/2), with prevailing AT1 expression. To study the role of renin-angiotensin system in the developmental programming of cardiac dysfunction, we assessed Ang receptor expression during neonatal high O2 exposure and whether AT1 receptor blockade prevents cardiac alterations in early adulthood. Sprague-Dawley newborn rats were kept with their mother in 80% O2 or room air (control) from days 3 to 10 (P3-P10) of life. Losartan or water was administered by gavage from P8 to P10 (n=9/group). Rats were studied at P3 (before O2 exposure), P5, P10 (end of O2), and P28. Losartan treatment had no impact on growth or kidney development. AT1 and Ang type 2 receptors were upregulated in the left ventricle by high O2 exposure (P5 and P10), which was prevented by Losartan treatment at P10. Losartan prevented the cardiac AT1/2 imbalance at P28. Losartan decreased cardiac hypertrophy and fibrosis and improved left ventricle fraction of shortening in P28 O2-exposed rats, which was associated with decreased oxidation of calcium/calmodulin-dependent protein kinase II, inhibition of the transforming growth factor-β/SMAD3 pathway, and upregulation of cardiac angiotensin-converting enzyme 2. In conclusion, short-term Ang II blockade during neonatal high O2 prevents the development of cardiac alterations later in life in rats. These findings highlight the key role of neonatal renin-angiotensin system activation in the developmental programming of cardiac dysfunction induced by deleterious neonatal conditions.

Postnatal acute renal failure after fetal exposure to angiotensin receptor blockers

Maternal hypertensive treatment with angiotensin receptor blockers (ARBs) during the second and third trimester of pregnancy is associated with several fetal and neonatal complications, and potential adverse outcomes. We report a neonate presenting with transient renal acute failure during the first days of life after maternal treatment with ARBs. Women who became pregnant while taking one of these drugs must modify antihypertensive therapy with a different class drug as soon as pregnancy is recognised.

Combination therapy in hypertension: an Asia-Pacific consensus viewpoint

Hypertension incurs a significant healthcare burden in Asia-Pacific countries, which have suboptimal rates of blood pressure (BP) treatment and control. A consensus meeting of hypertension experts from the Asia-Pacific region convened in Hanoi, Vietnam, in April 2013. The principal objectives were to discuss the growing problem of hypertension in the Asia-Pacific region, and to develop consensus recommendations to promote standards of care across the region. A particular focus was recommendations for combination therapy, since it is known that most patients with hypertension will require two or more antihypertensive drugs to achieve BP control, and also that combinations of drugs with complementary mechanisms of action achieve BP targets more effectively than monotherapy. The expert panel reviewed guidelines for hypertension management from the USA and Europe, as well as individual Asia-Pacific countries, and devised a treatment matrix/guide, in which they propose the preferred combination therapy regimens for patients with hypertension, both with and without compelling indications. This report summarizes key recommendations from the group, including recommended antihypertensive combinations for specific patient populations. These strategies generally entail initiating therapy with free drug combinations, starting with the lowest available dosage, followed by treatment with single-pill combinations once the BP target has been achieved. A single reference for the whole Asia-Pacific region may contribute to increased consistency of treatment and greater proportions of patients achieving BP control, and hence reducing hypertension-related morbidity and mortality.

Prenatal Exposure to Angiotensin II Receptor Blockers and Hemodynamic Effects on the Newborn

Angiotensin II receptor blockers (ARBs) are potent antihypertensive agents that block the renin angiotensin aldosterone system (RAS). Their use in pregnancy may cause malformations, oligoanuria, hypotension, and death. Hypotension is observed up to 15% of cases and is described as refractory to volume and inotropic support, although its pathophysiology is unknown. We present a case of prenatal exposure to ARBs in order to characterize the hemodynamic compromise in the newborn, help in decision-making, and guide the therapeutic approach to these patients.

Organic Anion Transporter 4-Mediated Transport of Olmesartan at Basal Plasma Membrane of Human Placental Barrier

Mechanisms regulating fetal transfer of olmesartan, an angiotensin-II receptor type 1 antagonist, are important as potential determinants of life-threatening adverse fetal effects. The purpose of this study was to examine the olmesartan transport mechanism through the basal plasma membrane (BM) of human syncytiotrophoblasts forming the placental barrier. Uptake of olmesartan by human placental BM vesicles was potently inhibited by dehydroepiandrosterone sulfate (DHEAS), estrone 3-sulfate, and bromosulfophthalein, which are all typical substrates of organic anion transporter (OAT) 4 localized at the BM of syncytiotrophoblasts, and was increased in the absence of chloride. In tetracycline-inducible OAT4-expressing cells, [(3) H]olmesartan uptake was increased by tetracycline treatment. Olmesartan uptake via OAT4 was concentration dependent with a Km of 20 μM, and was increased in the absence of chloride. [(3) H]Olmesartan efflux via OAT4 was also observed and was trans-stimulated by extracellular chloride and DHEAS. Thus, OAT4 mediates bidirectional transport of olmesartan and appears to regulate fetal transfer of olmesartan at the BM of syncytiotrophoblasts. Efflux transport of olmesartan via OAT4 from syncytiotrophoblasts to the fetal circulation might be facilitated in the presence of an inwardly directed physiological chloride gradient and extracellular DHEAS.

Renal function in angiotensinogen gene-mutated renal tubular dysgenesis with glomerular cysts

BACKGROUND

Inherited renal tubular dysgenesis (RTD) is caused by mutations in the genes encoding the components of the renin-angiotensin system (RAS). RTD is characterized by oligohydramnios, renal failure, neonatal hypocalvaria, and severe hypotension. The histological characteristics, underlying mechanism, and long-term prognosis remain poorly known.

CASE-DIAGNOSIS/TREATMENT

We describe here a 4-year-old female with RTD. Endocrinologic analysis showed a discrepancy between low plasma renin activity and high active renin concentration, suggesting a loss of the renin substrate, angiotensinogen (AGT). Direct sequencing revealed a frameshift deletion at nucleotide 1,355 in exon 5 in the AGT gene. Although a histological hallmark is regarded to be the absence or poor development of the proximal tubule, the patient does have minimally impaired function of the proximal tubule. Glomerular cysts without glomerular tufts were noted in approximately half of the glomeruli. The urinary concentrating ability and sodium reabsorption and potassium excretion in the distal nephron were severely affected.

CONCLUSIONS

The patient has an impaired function of the distal nephron despite minimally affected function of the proximal tubule, probably attributed to renal tubular dysgenesis and fetal hypoperfusion. The renal tubular maturity and the severity of ischemic injury may be key determinants of the clinical symptoms and pathological findings in RTD, in which the RAS plays an important role.

The relevance of the Renin-Angiotensin system in the development of drugs to combat preeclampsia

Preeclampsia is a hypertensive disorder that occurs during pregnancy. It has an unknown etiology and affects approximately 5-8% of pregnancies worldwide. The pathophysiology of preeclampsia is not yet known, and preeclampsia has been called "a disease of theories." The central symptom of preeclampsia is hypertension. However, the etiology of the hypertension is unknown. In this review, we analyze the molecular mechanisms of preeclampsia with a particular focus on the pathogenesis of the hypertension in preeclampsia and its association with the renin-angiotensin system. In addition, we propose potential alternative strategies to target the renin-angiotensin system, which is enhanced during pregnancy.

Renal teratogens

In utero exposure to certain drugs early in pregnancy may adversely affect nephrogenesis. Exposure to drugs later in pregnancy may affect the renin-angiotensin system, which could have an impact on fetal or neonatal renal function. Reduction in nephron number and renal function could have adverse consequences for the child several years later. Data are limited on the information needed to guide decisions for patients and providers regarding the use of certain drugs in pregnancy. The study of drug nephroteratogenicity has not been systematized, a large, standardized, global approach is needed to evaluate the renal risks of in utero drug exposures.

Absence of cell surface expression of human ACE leads to perinatal death

Renal tubular dysgenesis (RTD) is a recessive autosomal disease characterized most often by perinatal death. It is due to the inactivation of any of the major genes of the renin-angiotensin system (RAS), one of which is the angiotensin I-converting enzyme (ACE). ACE is present as a tissue-bound enzyme and circulates in plasma after its solubilization. In this report, we present the effect of different ACE mutations associated with RTD on ACE intracellular trafficking, secretion and enzymatic activity. One truncated mutant, R762X, responsible for neonatal death was found to be an enzymatically active, secreted form, not inserted in the plasma membrane. In contrast, another mutant, R1180P, was compatible with life after transient neonatal renal insufficiency. This mutant was located at the plasma membrane and rapidly secreted. These results highlight the importance of tissue-bound ACE versus circulating ACE and show that the total absence of cell surface expression of ACE is incompatible with life. In addition, two missense mutants (W594R and R828H) and two truncated mutants (Q1136X and G1145AX) were also studied. These mutants were neither inserted in the plasma membrane nor secreted. Finally, the structural implications of these ACE mutations were examined by molecular modelling, which suggested some important structural alterations such as disruption of intra-molecular non-covalent interactions (e.g. salt bridges).

How the kidney is impacted by the perinatal maternal environment to develop hypertension

Environmental conditions during perinatal development such as maternal undernutrition, maternal glucocorticoids, placental insufficiency, and maternal sodium overload can program changes in renal Na(+) excretion leading to hypertension. Experimental studies indicate that fetal exposure to an adverse maternal environment may reduce glomerular filtration rate by decreasing the surface area of the glomerular capillaries. Moreover, fetal responses to environmental insults during early life that contribute to the development of hypertension may include increased expression of tubular apical or basolateral membrane Na(+) transporters and increased production of renal superoxide leading to enhanced Na(+) reabsorption. This review will address the role of these potential renal mechanisms in the fetal programming of hypertension in experimental models induced by maternal undernutrition, fetal exposure to glucocorticoids, placental insufficiency, and maternal sodium overload in the rat.

Development of an automated imaging pipeline for the analysis of the zebrafish larval kidney

The analysis of kidney malformation caused by environmental influences during nephrogenesis or by hereditary nephropathies requires animal models allowing the in vivo observation of developmental processes. The zebrafish has emerged as a useful model system for the analysis of vertebrate organ development and function, and it is suitable for the identification of organotoxic or disease-modulating compounds on a larger scale. However, to fully exploit its potential in high content screening applications, dedicated protocols are required allowing the consistent visualization of inner organs such as the embryonic kidney. To this end, we developed a high content screening compatible pipeline for the automated imaging of standardized views of the developing pronephros in zebrafish larvae. Using a custom designed tool, cavities were generated in agarose coated microtiter plates allowing for accurate positioning and orientation of zebrafish larvae. This enabled the subsequent automated acquisition of stable and consistent dorsal views of pronephric kidneys. The established pipeline was applied in a pilot screen for the analysis of the impact of potentially nephrotoxic drugs on zebrafish pronephros development in the Tg(wt1b:EGFP) transgenic line in which the developing pronephros is highlighted by GFP expression. The consistent image data that was acquired allowed for quantification of gross morphological pronephric phenotypes, revealing concentration dependent effects of several compounds on nephrogenesis. In addition, applicability of the imaging pipeline was further confirmed in a morpholino based model for cilia-associated human genetic disorders associated with different intraflagellar transport genes. The developed tools and pipeline can be used to study various aspects in zebrafish kidney research, and can be readily adapted for the analysis of other organ systems.

Kidney disease in pregnancy: (Women's Health Series)

Kidney disease and pregnancy may exist in two general settings: acute kidney injury that develops during pregnancy, and chronic kidney disease that predates conception. In the first trimester of pregnancy, acute kidney injury is most often the result of hyperemesis gravidarum, ectopic pregnancy, or miscarriage. In the second and third trimesters, the common causes of acute kidney injury are severe preeclampsia, hemolysis-elevated liver enzymes-low platelets syndrome, acute fatty liver of pregnancy, and thrombotic microangiopathies, which may pose diagnostic challenges to the clinician. Cortical necrosis and obstructive uropathy are other conditions that may lead to acute kidney injury in these trimesters. Early recognition of these disorders is essential to timely treatment that can improve both maternal and fetal outcomes. In women with preexisting kidney disease, pregnancy-related outcomes depend upon the degree of renal impairment, the amount of proteinuria, and the severity of hypertension. Neonatal and maternal outcomes in pregnancies among renal transplant patients are generally good if the mother has normal baseline allograft function. Common renally active drugs and immunosuppressant medications must be prescribed, with special considerations in pregnant patients.

Diabetes and pregnancy: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to formulate a clinical practice guideline for the management of the pregnant woman with diabetes.

PARTICIPANTS

The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee of The Endocrine Society, 5 additional experts, a methodologist, and a medical writer.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence.

CONSENSUS PROCESS

One group meeting, several conference calls, and innumerable e-mail communications enabled consensus for all recommendations save one with a majority decision being employed for this single exception.

CONCLUSIONS

Using an evidence-based approach, this Diabetes and Pregnancy Clinical Practice Guideline addresses important clinical issues in the contemporary management of women with type 1 or type 2 diabetes preconceptionally, during pregnancy, and in the postpartum setting and in the diagnosis and management of women with gestational diabetes during and after pregnancy.

Rediscovering ACE: novel insights into the many roles of the angiotensin-converting enzyme

Angiotensin-converting enzyme (ACE) is best known for the catalytic conversion of angiotensin I to angiotensin II. However, the use of gene-targeting techniques has led to mouse models highlighting many other biochemical properties and actions of this enzyme. This review discusses recent studies examining the functional significance of ACE tissue-specific expression and the presence in ACE of two independent catalytic sites with distinct substrates and biological effects. It is these features which explain why ACE makes important contributions to many different physiological processes including renal development, blood pressure control, inflammation, and immunity.

New insights into the role of aminopeptidases in the treatment for both preeclampsia and preterm labor

INTRODUCTION

Evidence elucidating the pathophysiology and pharmacology of conventional drugs, β-2 stimulants and magnesium sulfate, on safety and effectiveness for preeclampsia and preterm labor are rarely found. Both compounds pass through the placental barrier and could exert their adverse effects on the fetus. Exposure to these agents could be problematic long after the birth, and possibly result in diseases such as autism and cardiomyopathy. Since 1970 the possible roles of placental aminopeptidases, which degrade peptide hormones, in preeclampsia and preterm labor have been studied.

AREAS COVERED

Many studies reveal that the fetus secretes peptide hormones, such as angiotensin II, vasopressin, and oxytocin, under hypoxia (stress) during the course of its growth, suggesting the critical effects these hormones have during pregnancy. The roles of placental aminopeptidases, the enzymes which degrade fetal hormones without passing through the placental barrier, were clarified. A first-step production system for recombinant aminopeptidases was established, by which engineered recombinant aminopeptidases were used for further experiments testing expected efficacy on controlling the level of hormones.

EXPERT OPINION

The authors conclude that both aminopeptidase A and placental leucine aminopeptidase could be potentially safe and effective drugs for patients and their babies in the treatment of preeclampsia and preterm labor.

Angiotensin-II receptor 1 antagonist fetopathy--risk assessment, critical time period and vena cava thrombosis as a possible new feature

AIMS

Angiotensin-II receptor 1 antagonists (AT₁-antagonists) may cause severe and even lethal fetopathy in late pregnancy. However, exposure still occurs in spite of warnings in package leaflets. This study aimed to assess the risk of fetopathy, the sensitive time window, and possible new symptoms in prospective as well as retrospective cases with AT₁-antagonist treatment during the second or third trimester of pregnancy.

METHODS

Patients were enrolled by the Berlin Institute for Clinical Teratology and Drug Risk Assessment in Pregnancy between 1999 and 2011 through risk consultation. Symptoms defined as indicative of AT₁-antagonist fetopathy were: oligo-/anhydramnios, renal insufficiency, lung hypoplasia, joint contractures, skull hypoplasia and fetal/neonatal death.

RESULTS

In 5/29 (17%) prospectively enrolled cases with AT₁-antagonist exposure beyond the first trimester oligo-/anhydramnios was diagnosed. Two infants showed additional symptoms of fetopathy. The risk is more than 30% if treatment continues beyond the 20th week of pregnancy. Oligo-/anhydramnios was reversible after AT₁-antagonist withdrawal. Among 16 retrospective case reports, three infants presented with a thrombosis of the inferior vena cava in the vicinity of the renal veins. Four out of 13 live births did not survive.

CONCLUSIONS

Our survey suggests that the risk increases with duration of AT₁-antagonist treatment into late pregnancy and oligo-/anhydramnios may be reversible after AT₁-antagonist discontinuation. Thrombosis of inferior vena cava may be a new feature of AT₁-antagonist fetopathy. AT₁-antagonist medication during pregnancy constitutes a considerable risk and must be discontinued immediately. In case of indicative diagnostic findings in either the fetus or newborn, previous maternal AT₁-antagonist exposure should be considered.

A modern understanding of the traditional and nontraditional biological functions of angiotensin-converting enzyme

Angiotensin-converting enzyme (ACE) is a zinc-dependent peptidase responsible for converting angiotensin I into the vasoconstrictor angiotensin II. However, ACE is a relatively nonspecific peptidase that is capable of cleaving a wide range of substrates. Because of this, ACE and its peptide substrates and products affect many physiologic processes, including blood pressure control, hematopoiesis, reproduction, renal development, renal function, and the immune response. The defining feature of ACE is that it is composed of two homologous and independently catalytic domains, the result of an ancient gene duplication, and ACE-like genes are widely distributed in nature. The two ACE catalytic domains contribute to the wide substrate diversity of ACE and, by extension, the physiologic impact of the enzyme. Several studies suggest that the two catalytic domains have different biologic functions. Recently, the X-ray crystal structure of ACE has elucidated some of the structural differences between the two ACE domains. This is important now that ACE domain-specific inhibitors have been synthesized and characterized. Once widely available, these reagents will undoubtedly be powerful tools for probing the physiologic actions of each ACE domain. In turn, this knowledge should allow clinicians to envision new therapies for diseases not currently treated with ACE inhibitors.

Stage 1 chronic kidney disease in pregnancy

Stage 1 chronic kidney disease (CKD) is defined by normal renal function, an estimated glomerular filtration rate of >90 mL/minute and abnormalities on urinalysis or ultrasound. These patients when pregnant are commonly seen, and diagnoses include diabetic nephropathy, glomerulonephritis, nephrolithiasis, reflux nephropathy, polycystic kidney disease and lupus nephritis. Underlying renal disease may also first become apparent in pregnancy, posing a diagnostic challenge. Patients tend to do well, but all need to be closely monitored particularly for hypertension and pre-eclampsia, which are more common in patients with stage 1 CKD overall. Relevant pregnancy outcomes may be divided into maternal (e.g. renal deterioration, nephrolithiasis, lupus flare, urinary infection or pyelonephritis), fetal (e.g. growth restriction, fetal death or stillbirth) and obstetric (e.g. hypertension, pre-eclampsia, preterm delivery, thrombosis). Specific diagnoses, their clinical features, management strategies and prognosis are reviewed.