95 research outputs found
11 β
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
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
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Age-Related Changes in the Natural Killer Cell Response to Seasonal Influenza Vaccination Are Not Influenced by a Synbiotic: a Randomised Controlled Trial
Natural killer (NK) cells are an important component of the immune response to influenza infection, but are subject to alteration during aging, which may play a role in impaired response to infection and vaccination in older people. Enhancement of NK cell activity could, therefore, present a means to improve the immune response to vaccination in older subjects, and pre- and probiotics offer an opportunity to modulate antiviral defenses via alteration of the gut microbiota. This study investigated the effect of a novel probiotic, Bifidobacterium longum bv. infantis CCUG 52486, combined with a prebiotic, gluco-oligosaccharide (B. longum + Gl-OS), on the NK cell response to seasonal influenza vaccination in young and older subjects in a double-blind, randomized controlled trial. There were significant effects of aging on NK cell phenotype, the most notable of which were an increase in CD56dim cells, mainly reflected in the CD16+ subset, a decrease in CD56bright cells, mainly reflected in the CD16− subset, and greater expression of the immunosenescence marker, CD57, on NK cell subsets. However, these changes only partially translated to differences in NK cell activity, observed as trends toward reduced NK cell activity in older subjects when analyzed on a per cell basis. Influenza vaccination increased the proportion of CD56bright cells and decreased the proportion of CD56dim cells, in young, but not older subjects. Although NK cell activity in response to vaccination was not significantly different between the young and older subjects, low post-vaccination NK cell activity was associated with poor seroconversion in only the older subjects. There was no influence of the synbiotic on NK cell phenotype or activity, either before or after influenza vaccination. In conclusion, aging is associated with marked alteration of the phenotype of the NK cell population and there was evidence of an impaired NK cell response to influenza vaccination in older subjects. The effects of aging on NK cell phenotype and activity could not be offset by B. longum + Gl-OS
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Impact of ageing and a synbiotic on the immune response to seasonal influenza vaccination; a randomised controlled trial
Background & aims
Ageing increases risk of respiratory infections and impairs the response to influenza vaccination. Pre- and pro-biotics offer an opportunity to modulate anti-viral defenses and the response to vaccination via alteration of the gut microbiota. This study investigated the effect of a novel probiotic, Bifidobacterium longum bv. infantis CCUG 52486, combined with a prebiotic, gluco-oligosaccharide, on the B and T cell response to seasonal influenza vaccination in young and older subjects .
Methods
In a double-blind, randomized controlled trial, 58 young (18–35 y) and 54 older (60–85 y) subjects were supplemented with the synbiotic for 8 weeks. At 4 weeks they were administered with a seasonal influenza vaccine. B and T cell phenotype and responsiveness to in vitro re-stimulation with the vaccine were assessed at baseline, 4, 6 and 8 weeks.
Results
B and T cell profiles differed markedly between young and older subjects. Vaccination increased numbers of memory, IgA+ memory, IgG+ memory and total IgG+ B cells in young subjects, but failed to do so in older subjects and did not significantly alter T cell subsets. Seroconversion to the H1N1 subunit in the older subjects was associated with higher post-vaccination numbers of plasma B cells, but seroconversion was less consistently associated with T cell phenotype. B and T cell subsets from both young and older subjects demonstrated a strong antigen-specific recall challenge, and although not influenced by age, responsiveness to the recall challenge was associated with seroconversion. In older subjects, CMV seropositivity was associated with a significantly lower recall response to the vaccine, but the synbiotic did not affect the responsiveness of B or T cells to re-stimulation with influenza vaccine.
Conclusions
Antigen-specific B and T cell activation following an in vitro recall challenge with the influenza vaccine was influenced by CMV seropositivity, but not by a synbiotic
The Plasma Membrane Calcium ATPases and Their Role as Major New Players in Human Disease.
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.
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
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.
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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