95 research outputs found

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    Preeclampsia is a serious medical problem affecting the mother and her child and influences their health not only during the pregnancy, but also many years after. Although preeclampsia is a subject of many research projects, the etiology of the condition remains unclear. One of the hypotheses related to the etiology of preeclampsia is the deficiency in placental 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2), the enzyme which in normal pregnancy protects the fetus from the excess of maternal cortisol. The reduced activity of the enzyme was observed in placentas from pregnancies complicated with preeclampsia. That suggests the overexposure of the developing child to maternal cortisol, which in high levels exerts proapoptotic effects and reduces fetal growth. The fetal growth restriction due to the diminished placental 11β-HSD2 function may be supported by the fact that preeclampsia is often accompanied with fetal hypotrophy. The causes of the reduced function of 11β-HSD2 in placental tissue are still discussed. This paper summarizes the phenomena that may affect the activity of the enzyme at various steps on the way from the gene to the protein

    Glucocorticoids action in etiology of hypertension

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    Glikokortykosteroidy (GKS), z których kluczową rolę pełni kortyzol (F), odgrywają wiele istotnych funkcji metabolicznych, przede wszystkim w regulacji stężenia glukozy czy wpływie na przemiany białek i tłuszczy. Zwiększona sekrecja F lub jego nieprawidłowy metabolizm lub zwiększona wrażliwość tkanek na działanie GKS może prowadzić do powstawania zaburzeń metabolicznych i wielu chorób, między innymi nadciśnienia tętniczego. Kluczowym enzymem w metabolizmie F jest dehydrogenaza 11β-hydroksysteroidowa, która katalizuje wzajemne przekształcenie aktywnego biologicznie F i nieczynnego kortyzonu. Izoforma 2 tego enzymu odpowiada za ochronę receptora mineralokortykosteroidowego przed działaniem F. W przypadku defektu jej aktywności, między innymi w zespole pozornego nadmiaru mineralokortykosteroidów, dochodzi do pobudzenia MR przez F, zwiększenia objętości płynów w łożysku naczyniowym i w konsekwencji do nadciśnienia tętniczego. Innym potencjalnym mechanizmem hipertensyjnego działania GKS jest wpływ na syntezę tlenku azotu (NO). Obniżenie stężenia NO, głównego czynnika rozszerzającego naczynia krwionośne, zachodzi między innymi na drodze hamowania ekspresji izoformy 2 i 3 syntazy tlenku azotu, niekorzystnego wpływu na dostępność niezbędnego kofaktora oraz poprzez zmniejszenie poziomu substratu do syntezy NO. W pracy przedstawiono aktualne dane z piśmiennictwa dotyczące udziału GKS w patogenezie nadciśnienia tętniczego.Glucocorticoids (GKS), among which cortisol (F) is the most important factor, have various metabolic functions. They regulate glucose levels and influence proteins and lipids metabolism. Higher secretion of F, its changed metabolism or higher sensitivity of cells or tissues to F might be a source of metabolic disorders and many diseases, inter alia arterial hypertension. The key enzyme in F metabolism is 11b-hydroxysteroid dehydrogenase, which catalyzes the interconversion of F and inactive cortisone. The isoform 2 of that enzyme (11β-HSD2) is responsible for mineralocorticoid receptor’s protection from F. Disturbances in activity of 11β-HSD2, for example in apparent mineralocorticoid excess, lead to mineralocorticoid receptor activation by F, water retention and finally to hypertension. The influence of GKS on nitric oxide (NO) synthesis is another possible mechanism of hypertensive action of GKS. Decrease of NO levels may be an effect of inhibition of expression of nitric oxide synthase isoform 2 and 3, lack of enzyme co-factor or the substrate for NO synthesis. The paper summarises data considering GKS influence on pathomechanism of arterial hypertension. Arterial Hypertension 2010, vol. 14, no 3, pages 208-21

    The Plasma Membrane Calcium ATPases and Their Role as Major New Players in Human Disease.

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    The Ca2+ extrusion function of the four mammalian isoforms of the plasma membrane calcium ATPases (PMCAs) is well established. There is also ever-increasing detail known of their roles in global and local Ca2+ homeostasis and intracellular Ca2+ signaling in a wide variety of cell types and tissues. It is becoming clear that the spatiotemporal patterns of expression of the PMCAs and the fact that their abundances and relative expression levels vary from cell type to cell type both reflect and impact on their specific functions in these cells. Over recent years it has become increasingly apparent that these genes have potentially significant roles in human health and disease, with PMCAs1-4 being associated with cardiovascular diseases, deafness, autism, ataxia, adenoma, and malarial resistance. This review will bring together evidence of the variety of tissue-specific functions of PMCAs and will highlight the roles these genes play in regulating normal physiological functions and the considerable impact the genes have on human disease

    Mimicry and well known genetic friends: molecular diagnosis in an Iranian cohort of suspected Bartter syndrome and proposition of an algorithm for clinical differential diagnosis.

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    BACKGROUND: Bartter Syndrome is a rare, genetically heterogeneous, mainly autosomal recessively inherited condition characterized by hypochloremic hypokalemic metabolic alkalosis. Mutations in several genes encoding for ion channels localizing to the renal tubules including SLC12A1, KCNJ1, BSND, CLCNKA, CLCNKB, MAGED2 and CASR have been identified as underlying molecular cause. No genetically defined cases have been described in the Iranian population to date. Like for other rare genetic disorders, implementation of Next Generation Sequencing (NGS) technologies has greatly facilitated genetic diagnostics and counseling over the last years. In this study, we describe the clinical, biochemical and genetic characteristics of patients from 15 Iranian families with a clinical diagnosis of Bartter Syndrome. RESULTS: Age range of patients included in this study was 3 months to 6 years and all patients showed hypokalemic metabolic alkalosis. 3 patients additionally displayed hypercalciuria, with evidence of nephrocalcinosis in one case. Screening by Whole Exome Sequencing (WES) and long range PCR revealed that 12/17 patients (70%) had a deletion of the entire CLCNKB gene that was previously identified as the most common cause of Bartter Syndrome in other populations. 4/17 individuals (approximately 25% of cases) were found to suffer in fact from pseudo-Bartter syndrome resulting from congenital chloride diarrhea due to a novel homozygous mutation in the SLC26A3 gene, Pendred syndrome due to a known homozygous mutation in SLC26A4, Cystic Fibrosis (CF) due to a novel mutation in CFTR and apparent mineralocorticoid excess syndrome due to a novel homozygous loss of function mutation in HSD11B2 gene. 1 case (5%) remained unsolved. CONCLUSIONS: Our findings demonstrate deletion of CLCNKB is the most common cause of Bartter syndrome in Iranian patients and we show that age of onset of clinical symptoms as well as clinical features amongst those patients are variable. Further, using WES we were able to prove that nearly 1/4 patients in fact suffered from Pseudo-Bartter Syndrome, reversing the initial clinical diagnosis with important impact on the subsequent treatment and clinical follow up pathway. Finally, we propose an algorithm for clinical differential diagnosis of Bartter Syndrome

    The restorative role of annexin A1 at the blood–brain barrier

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    Annexin A1 is a potent anti-inflammatory molecule that has been extensively studied in the peripheral immune system, but has not as yet been exploited as a therapeutic target/agent. In the last decade, we have undertaken the study of this molecule in the central nervous system (CNS), focusing particularly on the primary interface between the peripheral body and CNS: the blood–brain barrier. In this review, we provide an overview of the role of this molecule in the brain, with a particular emphasis on its functions in the endothelium of the blood–brain barrier, and the protective actions the molecule may exert in neuroinflammatory, neurovascular and metabolic disease. We focus on the possible new therapeutic avenues opened up by an increased understanding of the role of annexin A1 in the CNS vasculature, and its potential for repairing blood–brain barrier damage in disease and aging

    Psychosocial impact of undergoing prostate cancer screening for men with BRCA1 or BRCA2 mutations.

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    OBJECTIVES: To report the baseline results of a longitudinal psychosocial study that forms part of the IMPACT study, a multi-national investigation of targeted prostate cancer (PCa) screening among men with a known pathogenic germline mutation in the BRCA1 or BRCA2 genes. PARTICPANTS AND METHODS: Men enrolled in the IMPACT study were invited to complete a questionnaire at collaborating sites prior to each annual screening visit. The questionnaire included sociodemographic characteristics and the following measures: the Hospital Anxiety and Depression Scale (HADS), Impact of Event Scale (IES), 36-item short-form health survey (SF-36), Memorial Anxiety Scale for Prostate Cancer, Cancer Worry Scale-Revised, risk perception and knowledge. The results of the baseline questionnaire are presented. RESULTS: A total of 432 men completed questionnaires: 98 and 160 had mutations in BRCA1 and BRCA2 genes, respectively, and 174 were controls (familial mutation negative). Participants' perception of PCa risk was influenced by genetic status. Knowledge levels were high and unrelated to genetic status. Mean scores for the HADS and SF-36 were within reported general population norms and mean IES scores were within normal range. IES mean intrusion and avoidance scores were significantly higher in BRCA1/BRCA2 carriers than in controls and were higher in men with increased PCa risk perception. At the multivariate level, risk perception contributed more significantly to variance in IES scores than genetic status. CONCLUSION: This is the first study to report the psychosocial profile of men with BRCA1/BRCA2 mutations undergoing PCa screening. No clinically concerning levels of general or cancer-specific distress or poor quality of life were detected in the cohort as a whole. A small subset of participants reported higher levels of distress, suggesting the need for healthcare professionals offering PCa screening to identify these risk factors and offer additional information and support to men seeking PCa screening
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