In-depth review: is hepcidin a marker for the heart and the kidney?

Iron is an essential trace element involved in oxidation–reduction reactions, oxygen transport and storage, and energy metabolism. Iron in excess can be toxic for cells, since iron produces reactive oxygen species and is important for survival of pathogenic microbes. There is a fine-tuning in the regulation of serum iron levels, determined by intestinal absorption, macrophage iron recycling, and mobilization of hepatocyte stores versus iron utilization, primarily by erythroid cells in the bone marrow. Hepcidin is the major regulatory hormone of systemic iron homeostasis and is upregulated during inflammation. Hepcidin metabolism is altered in chronic kidney disease. Ferroportin is an iron export protein and mediates iron release into the circulation from duodenal enterocytes, splenic reticuloendothelial macrophages, and hepatocytes. Systemic iron homeostasis is controlled by the hepcidin–ferroportin axis at the sites of iron entry into the circulation. Hepcidin binds to ferroportin, induces its internalization and intracellular degradation, and thus inhibits iron absorption from enterocytes, and iron release from macrophages and hepatocytes. Recent data suggest that hepcidin, by slowing or preventing the mobilization of iron from macrophages, may promote atherosclerosis and may be associated with increased cardiovascular disease risk. This article reviews the current data regarding the molecular and cellular pathways of systemic and autocrine hepcidin production and seeks the answer to the question whether changes in hepcidin translate into clinical outcomes of all-cause and cardiovascular mortality, and cardiovascular and renal end-points.

     

Evaluation of the therapeutic potential effect of Fas receptor gene knockdown in experimental model of non-alcoholic steatohepatitis

Aim: Stimulation of Fas death receptor is introduced as a major cause of non-alcoholic steatohepatitis (NASH) progression through suppression of cell viability. Therefore, the blocking of death pathways is hypothesised to be express new approaches to NASH therapy. For this purpose, current experiment applied synthetic small interference RNA (SiRNA) to trigger Fas death receptor and to show its potential therapeutic role in designed NASH model.

Methods: Male mice were placed on a western diet (WD) for 8 weeks and exposed to cigarette smoke during the last 4 weeks of feeding to induce NASH model. In the next step, Fas SiRNA was injected to mice aiming to examine specific Fas gene silencing, after 8 weeks. As a control, mice received scrambled SiRNA. Reversible possibility of disease was examined by 3 weeks of recovery.

Results: Analysis of data is accompanied with the significant histopathological changes (steatosis, ballooning and inflammation), increased lipid profile and hepatic enzyme activities (AST, ALT, ALP) plus TBARS as well as decreased antioxidants levels in NASH model. Upon Fas-SiRNA injection, almost all measured parameters of NASH such as overexpression of Fas receptor, caspase3, NF-kB genes and marked increase of hepatic TNF-α were significantly restored and were remained nearly unchanged following recovery liking as scrambled groups.

Conclusions: The suppression of Fas receptor signalling subsequent RNAi therapy may represent an applicable strategy to decline hepatocyte damages and so NASH progression in mice.     

Uric Acid Induces Hepatic Steatosis by Generation of Mitochondrial Oxidative Stress: POTENTIAL ROLE IN FRUCTOSE-DEPENDENT AND -INDEPENDENT FATTY LIVER*

Metabolic syndrome represents a collection of abnormalities that includes fatty liver, and it currently affects one-third of the United States population and has become a major health concern worldwide. Fructose intake, primarily from added sugars in soft drinks, can induce fatty liver in animals and is epidemiologically associated with nonalcoholic fatty liver disease in humans. Fructose is considered lipogenic due to its ability to generate triglycerides as a direct consequence of the metabolism of the fructose molecule. Here, we show that fructose also stimulates triglyceride synthesis via a purine-degrading pathway that is triggered from the rapid phosphorylation of fructose by fructokinase. Generated AMP enters into the purine degradation pathway through the activation of AMP deaminase resulting in uric acid production and the generation of mitochondrial oxidants. Mitochondrial oxidative stress results in the inhibition of aconitase in the Krebs cycle, resulting in the accumulation of citrate and the stimulation of ATP citrate lyase and fatty-acid synthase leading to de novo lipogeneis. These studies provide new insights into the pathogenesis of hepatic fat accumulation under normal and diseased states.     

Survival of acid-adapted and non-adaptedStaphylococcus aureus in various food samples

Resistance ofStaphylococcus aureus to acid pH was studied.Staphylococcus aureus ATCC 6538 was acid-adapted at pH 5.0 in tryptic soy broth (TSB) for 4 h. Commercial products, mayonnaise pH 3.57, rape pH 3.72, fatty yogurt pH 4.01, were purchased from a local supermarket, and kisir köfte pH 4.9 samples were prepared by us. All of the samples were inoculated with acid-adapted or non-adapted cells ofS. aureus. In un-inoculated mayonnaise, rape, fatty yogurt, and kisir köfteS. aureus was not detected. The viable population of S. aureus in mayonnaise declined quickly when stored at 4 or 25 °C. After 48 h of storage, no viable cells were recovered from mayonnaise inoculated with acid-adapted or non-adapted ATCC 6538 at 25 °C. Acid-adapted cells were recovered in greater numbers than non-adapted cells during storage at 4 or 25 °C. After 24 h of storage, no viable cells were recovered from rape and yogurt inoculated with acid-adapted and non-adapted ATCC 6538 at 4 and 25 °C. Acid-adaptedS. aureus survived in kisir köfte during 48 h. After 72 h of storage, no viable cells were recovered from kisir köfte inoculated with acid-adapted and non-adapted ATCC 6538 at 25 °C and 4 °C.     

Overhydration,Cardiac Function and Survival in Hemodialysis Patients

Background and objectives

Chronic subclinical volume overload occurs very frequently and may be ubiquitous in hemodialysis (HD) patients receiving the standard thrice-weekly treatment. It is directly associated with hypertension, increased arterial stiffness, left ventricular hipertrophy, heart failure, and eventually, higher mortality and morbidity. We aimed to assess for the first time if the relationship between bioimpedance assessed overhydration and survival is maintained when adjustments for echocardiographic parameters are considered.

Design, setting, participants and measurements

A prospective cohort trial was conducted to investigate the impact of overhydration on all cause mortality and cardiovascular events (CVE), by using a previously reported cut-off value for overhydration and also investigating a new cut-off value derived from our analysis of this specific cohort. The body composition of 221 HD patients from a single center was assessed at baseline using bioimpedance. In 157 patients supplemental echocardiography was performed (echocardiography subgroup). Comparative survival analysis was performed using two cut-off points for relative fluid overload (RFO): 15% and 17.4% (a value determined by statistical analysis to have the best predictive value for mortality in our cohort).

Results

In the entire study population, patients considered overhydrated (using both cut-offs) had a significant increased risk for all-cause mortality in both univariate (HR = 2.12, 95%CI = 1.30–3.47 for RFO>15% and HR = 2.86, 95%CI = 1.72–4.78 for RFO>17.4%, respectively) and multivariate (HR = 1.87, 95%CI = 1.12–3.13 for RFO>15% and HR = 2.72, 95%CI = 1.60–4.63 for RFO>17.4%, respectively) Cox survival analysis. In the echocardiography subgroup, only the 17.4% cut-off remained associated with the outcome after adjustment for different echocardiographic parameters in the multivariate survival analysis. The number of CVE was significantly higher in overhydrated patients in both univariate (HR = 2.46, 95%CI = 1.56–3.87 for RFO >15% and HR = 3.67, 95%CI = 2.29–5.89 for RFO >17.4%) and multivariate (HR = 2.31, 95%CI = 1.42–3.77 for RFO >15% and HR = 4.17, 95%CI = 2.48–7.02 for RFO >17.4%) Cox regression analysis.

Conclusions

The study shows that the hydration status is associated with the mortality risk in a HD population, independently of cardiac morphology and function. We also describe and propose a new cut-off for RFO, in order to better define the relationship between overhydration and mortality risk. Further studies are needed to properly validate this new cut-off in other HD populations.     

Bone Marrow-Derived Stem Cell (BMDSC) Transplantation Improves Fertility in a Murine Model of Asherman's Syndrome

Asherman''s Syndrome is characterized by intrauterine adhesions or fibrosis resulting as a consequence of damage to the basal layer of endometrium and is associated with infertility due to loss of normal endometrium. We have previously shown that bone marrow derived stem cells (BMDSCs) engraft the endometrium in mice and humans and Ischemia/reperfusion injury of uterus promoted BMDSCs migration to the endometrium; however, the role of BMDSCs in Asherman''s syndrome has not been characterized. Here a murine model of Asherman''s syndrome was created by traumatizing the uterus. We evaluate stem cell recruitment and pregnancy after BMDSCs transplantation in a model of Asherman''s syndrome. In the Asheman''s syndrome model, after BMDSC transplant, the Y chromosome bearing CD45-cells represented less than 0.1% of total endometrial cells. Twice the number of Y+CD45- cells was identified in the damaged uterus compared to the uninjured controls. There was no significant difference between the damaged and undamaged uterine horns in mice that received injury to a single horn. In the BMDSC transplant group, 9 of the 10 mice conceived, while only 3 of 10 in the non-transplanted group conceived (Chi-Square p = 0.0225); all mice in an uninjured control group conceived. The time to conception and mean litter size were not different between groups. Taken together, BMDSCs are recruited to endometrium in response to injury. Fertility improves after BMDSC transplant in Asherman''s Syndrome mice, demonstrating a functional role for these cells in uterine repair. BMDSC transplantation is a potential novel treatment for Asherman''s Syndrome and may also be useful to prevent Asherman''s syndrome after uterine injury.     

The frequency of Familial Mediterranean fever gene mutations and genotypes at Kirikkale and comparison with the mean of regional MEFV mutation frequency of Turkey

In this study we have retrospectively analysed the mutation spectrum of the 351 Familial Mediterranean fever patients referred to K?r?kkale University Faculty of Medicine, Department of Medical Genetics Laboratory over a period of 5 years and compared them with Turkey’s mean. We have found 11 different mutations, including rare mutations such as F479L, K695R, M680I(G/A) and 45 different genotypes showing the heterogeneity of MEFV mutations in Central Anatolia. The most three prevalent mutations were M694V (14.8 %), E148Q (7.1 %) and M680I(G/C) (4.1 %) in accordance with the literature. We have also investigated R202Q in our routine molecular diagnosis. Mutation causing R202Q (c.605G > A) change was described as a frequent polymorphism and G allele was found in linkage disequilibrium (LD) with M694V. There are limited number of studies investigating R202Q, some of them implicate that its homozygote state is disease causing. We showed the high frequency of R202Q (23.7 %) with and without M694V in all the groups analysed and its high LD rate with M694V in the diagnosed group. Our study is reflecting the mutational heterogeneity of MEFV and summarize mutational spectrum of Turkey’s geographical regions and overall Turkey.     

Association between 1603C>T polymorphism of DBH gene and bipolar disorder in a Turkish population

Objectives

Dopamine-β-hydroxylase (DBH) is the enzyme responsible for the conversion of dopamine (DA) to norepinephrine (NE, noradrenaline) which is a key neurotransmitter in the central and peripheral nervous systems. Bipolar disorder is a major psychiatric disorder. The present study was designed to explore the associations of polymorphisms of DBH gene in Turkish patients with bipolar disorder.

Methods

− 1021C>T (rs1611115) polymorphism in promoter region, 444G>A (rs1108580) polymorphism in exon 2 and 1603C>T (rs6271; C535R) polymorphism in exon11 of DBH gene were analyzed in 106 patients with bipolar disorder and 106 healthy subjects by using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis.

Results

The results showed statistically significant associations for genotypic and allelic distribution between the 1603C>T polymorphism and bipolar disease (p = 0.0012 and p = 0.034, respectively). There was no association observed between the genotype and allelic frequencies for − 1021C>T and 444G>A polymorphisms and bipolar disorder.

Conclusions

Our data suggests that the 1603C>T polymorphism of the DBH gene is associated with susceptibility to bipolar disorder in a Turkish population.     

DNA splicing of mitochondrial group I and II introns in Schizosaccharomyces pombe

Summary In this paper we report the precise excision of the group I intron aI2b from the cox1 gene and of the group II intron bI from the cob gene fo the Schizosaccharomyces pombe strain 50. We present evidence that DNA excision of both intron DNA sequences is under nuclear control. Attempts to remove the first cox1 intron (aI1) have failed so far, but a deletion of approximately 200 bp in the open intronic reading frame demonstrates that it is not essential for normal cellular functions.Abbreviations cox1, cox2, cox3 genes encoding subunits 1, 2 and 3 of cytochrome c oxidase - cob gene encoding apocytochrome b - rns and rnl genes encoding the small and large ribosomal RNA - atp6, atp8 and atp9 genes encoding subunits 6, 8, and 9 of the ATP synthase complex - urfa unassigned reading frame a - aI1, aI2a, aI2b, aI3 introns in the cox 1 gene of S. pombe - bI intron in the cob gene - del-aI2b and del-bI respiratory competent strains in which the respective introns have been deleted by DNA splicing