A novel LMNA mutation (R189W) in familial dilated cardiomyopathy: evidence for a 'hot spot' region at exon 3: a case report

Background

To assess the reliability of fetal heart volume measurement by three-dimensional sonography (3DUS) using the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) method.

Methods

This reliability study enrolled 30 pregnant women with singleton healthy pregnancies between 19 and 34 weeks of gestation. All volume acquirements were performed with a convex volumetric transducer (C3-7ED) coupled to an Accuvix XQ sonography device (Medison, Korea). The XI VOCAL 10 planes was the method of choice for volumetric measurement. 3D datasets were analyzed by two observers (EQSB and HJFM); fetal heart volume was measured twice by the first and once by the second observer to calculate intra and interobserver reproducibility. Statistical analysis used pareated Student's t test (p) and calculated Intraclass correlation coefficients (ICC). Bland-Altman plots were also constructed.

Results

We observed an excellent intra- and interobserver reliability for fetal cardiac volume assessed by XI VOCAL. For the intraobserver the ICC was 0.998 (95% CI: 0.997; 0.999), with mean of differences of 0.12 cm³ (95% limits of agreement: -0.84; +0.84; p = 0.130). For interobserver the ICC was 0.899 (95%CI: 0.996; 0.998), mean of differences 0.05 cm³ (95% limits of agreement: -0.84; +0.84; p = 0.175).

Conclusion

Fetal cardiac volume assessed by 3DUS using XI VOCAL method is highly reproducible between 19 to 34 gestational weeks.     

Fasting and differential chemotherapy protection in patients

Chronic calorie restriction has been known for decades to prevent or retard cancer growth, but its weight-loss effect and the potential problems associated with combining it with chemotherapy have prevented its clinical application. Based on the discovery in model organisms that short term starvation (STS or fasting) causes a rapid switch of cells to a protected mode, we described a fasting-based intervention that causes remarkable changes in the levels of glucose, IGF-I and many other proteins and molecules and is capable of protecting mammalian cells and mice from various toxins, including chemotherapy. Because oncogenes prevent the cellular switch to this stress resistance mode, starvation for 48 hours or longer protects normal yeast and mammalian cells and mice but not cancer cells from chemotherapy, an effect we termed Differential Stress Resistance (DSR). In a recent article, ten patients who fasted in combination with chemotherapy, reported that fasting was not only feasible and safe but caused a reduction in a wide range of side effects accompanied by an apparently normal and possibly augmented chemotherapy efficacy. Together with the remarkable results observed in animals, these data provide preliminary evidence in support of the human application of this fundamental biogerontology finding, particularly for terminal patients receiving chemotherapy. Here we briefly discuss the basic, pre-clinical and clinical studies on fasting and cancer therapy.Key words: fasting, cancer, chemotherapy, calorie restriction, stress resistanceAfter decades of slow progress in the identification of treatments effective on a wide range of malignancies, cancer treatment is now turning to personalized therapies based in part on pharmacogenomics. By contrast, aging research is moving in the opposite direction by searching for common ways to prevent, postpone and treat a wide range of age-related diseases, based on the modulation of genetic pathways that are conserved from yeast to mammals.¹ In fact, it may be a solid evolutionary and comparative biology-foundation, which makes this ambitious goal of biogerontologists a realistic or at least a promising one. On the other hand, the progress of biogerontology is viewed by many clinicians as too fundamental and far from translational applications. In most cases, it is not clear how aging research will be translated into FDA approved drugs or treatments that have effects that are superior to those already available or being developed. For example, it is not clear how the long-term 20–30% reduction in calorie intake (dietary restriction, DR) that we and many others before us have shown to be effective in extending the life span of model organisms will make humans live longer or healthier.^1–3 Furthermore, despite the fact that long-term DR was confirmed to reduce cancer and cardiovascular disease in monkeys⁴ and to be effective in preventing obesity, type 2 diabetes, inflammation, hypertension and atherosclerosis, as indicated by the early results in humans studies,⁵ it is highly unlikely to be adopted in its more extreme and effective version by even a small portion of the population. For example, the 20 to 40% chronic reduction in daily calorie intake shown to be effective in retarding cancer growth in mice would not be feasible for cancer therapy for multiple reasons: (1) the effects of chronic DR in patients with a clinically evident tumor is expected to delay but not stop the progression of the disease^6–8 and this delay may only occur for a portion of the malignancies,⁹ (2) although weight loss and cachexia in the early stages of treatment are less prevalent than commonly thought,^10–12 the ∼15% loss of BMI and ∼30% long-term loss of body fat caused by a moderate (20%) calorie restriction¹³ may be tolerated by only a very small portion of cancer patients receiving treatment, (3) Because this long-term restriction is accompanied by delayed wound healing and immunologic impairment in rodents,^1,14,15 it is not clear what risks it may impose on cancer patients receiving treatment.¹⁶ Our studies of DSR, which were triggered by our fundamental findings that switching yeast cells to water protected them against a wide range of toxins, started as a way to address these concerns but also as an attempt to achieve a much more potent therapeutic effect than that achieved by DR.^17,18 Because starvation-induced protection can increase many fold when combined with modulation of pro-aging pathways and since it is in principle blocked by the expression of any oncogene, it has the potential to provide a method to allow common chemotherapy to selectively kill cancer cells, independently of the type of cancer.^19–21 The DSR experiments in mammals were also based on our hypothesis that stress resistance and aging regulatory pathways were conserved from yeast to mammals.We found that fasting for 48 or more hours or in vitro starvation conditions that mimic fasting protected mice and/or normal cells but not cancer cells from various chemotherapy drugs and other deleterious agents.²¹ This effect was shown to depend in part on the reduction of circulating IGF-I and glucose levels.^21,22 Although a differential regulation of cell division in normal and cancer cells^23,24 is likely to contribute to DSR, much of it appears to be dependent on protective systems which are normally maintained in an inactive or low activity state even in non-dividing cells.^1,25 In fact, in non-dividing yeast and mice, deficiencies in glucose or IGF-I signaling that match those observed after starvation promote resistance to doxorubicin, a chemotherapy drug that specifically targets muscle cells in the heart.^21,22As expected, many clinicians were skeptical of our hypothesis that cancer treatment could be improved not by a “magic bullet” but by a “not so magic DSR shield” as underlined by Leonard Saltz, an oncologist at Memorial Sloan-Kettering Cancer Center: “Would I be enthusiastic about enrolling my patients in a trial where they''re asked not to eat for 2.5 days? No.”²⁶ However, ten oncologists did allow their patients, suffering from malignancies ranging from stage II breast cancer to stage IV esophageal, prostate and lung malignancies to undergo a 48–140 hours pre-chemotherapy and a 5–56 hours post chemotherapy water-only fast. The six patients who received chemotherapy with or without fasting reported a reduction in fatigue, weakness and gastrointestinal side effects while fasting²⁷ (Fig. 1). A trend for a reduction of many additional side effects was also reported by the group of patients who always fasted before chemotherapy.²⁷ In those patients whose cancer progression was assessed, chemotherapy was effective and in some cases it was highly effective.²⁷ A clinical trial sponsored by the V-Foundation for Cancer Research, aimed at testing the safety and efficacy of a 24 hour fast in combination with chemotherapy, is in its safety stage. Because it was originally limited to patients diagnosed with bladder cancer the clinical trial progressed slowly. However, its recent expansion to include patients receiving platinum-based chemotherapy (breast, ovarian, lung cancer), is expected to expedite it. Conclusive results for the effect of a 3–4 day fast on chemotherapy-dependent side effects and possibly therapeutic index are not expected to become available for several years. Even if a more modest effect than the 1,000-fold differential protection against oxidative stress and chemotherapy observed in normal and cancer-like yeast cells was achieved in humans, this method could result in long-term survival for many patients with metastatic cancers, particularly those in which malignant cells have not acquired multidrug resistance.Open in a separate windowFigure 1Average self-reported severity of symptoms in patients that have received chemotherapy with or without fasting.     

Uric acid levels are associated with endothelial dysfunction and severity of coronary atherosclerosis during a first episode of acute coronary syndrome

The role of serum uric acid in coronary artery disease has been extensively investigated. It was suggested that serum uric acid level (SUA) is an independent predictor of endothelial dysfunction and related to coronary artery lesions. However, the relationship between SUA and severity of coronary atherosclerosis evaluated via endothelial dysfunction using peripheral arterial tone (PAT) and the reactive hyperhemia index (RHI) has not been investigated during a first episode of acute coronary syndrome (ACS). The aim of our study was to address this point. We prospectively enrolled 80 patients with a first episode of ACS in a single-center observational study. All patients underwent coronary angiography, evaluation of endothelial function via the RHI, and SUA measurement. The severity of the coronary artery lesion was assessed angiographically, and patients were classified in three groups based on the extent of disease and Gensini and SYNTAX scores. Endothelial function was considered abnormal if RHI?<?1.67. We identified a linear correlation between SUA and RHI (R² =?0.66 P <?0.001). In multivariable analyses, SUA remained associated with RHI, even after adjustment for traditional cardiovascular risk factors and renal function. SUA was associated with severity of coronary artery disease. SUA is associated with severity of coronary atherosclerosis in patients with asymptomatic hyperuricemia. This inexpensive, readily measured biological parameter may be useful to monitor ACS patients.     

2,3,7,8-Tetrachlorodibenzo-p-dioxin impairs iron homeostasis by modulating iron-related proteins expression and increasing the labile iron pool in mammalian cells

Cellular iron metabolism is essentially controlled by the binding of cytosolic iron regulatory proteins (IRP1 or IRP2) to iron-responsive elements (IREs) located on mRNAs coding for proteins involved in iron acquisition, utilization and storage. The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is one of the most potent toxins of current interest that occurs as poisonous chemical in the environment. TCDD exposure has been reported to induce a broad spectrum of toxic and biological responses, including significant changes in gene expression for heme and iron metabolism associated with liver injury. Here, we have investigated the molecular effects of TCDD on the iron metabolism providing the first evidence that administration of the toxin TCDD to mammalian cells affects the maintenance of iron homeostasis. We found that exposure of Madin-Darby Bovine Kidney cell to TCDD caused a divergent modulation of IRP1 and IRP2 RNA-binding capacity. Interestingly, we observed a concomitant IRP1 down-regulation and IRP2 up-regulation thus determining a marked enhancement of transferrin receptor 1 (TfR-1) expression and a biphasic response in ferritin content. The changed ferritin content coupled to TfR-1 induction after TCDD exposure impairs the cellular iron homeostasis, ultimately leading to significant changes in the labile iron pool (LIP) extent. Since important iron requirement changes occur during the regulation of cell growth, it is not surprising that the dioxin-dependent iron metabolism dysregulation herein described may be linked to cell-fate decision, supporting the hypothesis of a central connection among exposure to dioxins and the regulation of critical cellular processes. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.     

UCP2 protects hypothalamic cells from TNF-alpha-induced damage

Uncoupling protein 2 (UCP2) is highly expressed in the hypothalamus; however, little is known about the functions it exerts in this part of the brain. Here, we hypothesized that UCP2 protects hypothalamic cells from oxidative and pro-apoptotic damage generated by inflammatory stimuli. Intracerebroventricular injection of tumor necrosis factor alpha (TNF-alpha)-induced an increase of UCP2 expression in the hypothalamus, which was accompanied by increased expression of markers of oxidative stress and pro-apoptotic proteins. The inhibition of UCP2 expression by an antisense oligonucleotide enhanced the damaging effects of TNF-alpha. Conversely, increasing the hypothalamic expression of UCP2 by cold exposure reversed most of the effects of the cytokine. Thus, UCP2 acts as a protective factor against cellular damage induced by an inflammatory stimulus in the hypothalamus.     

Salivary gland proteins alterations in the diabetic milieu

Journal of Molecular Histology - Salivary glands are considered the chief exocrine glands of the mouth and physiologically contribute to the maintenance of the homeostasis of the oral cavity. They...     

Familial partial lipodystrophy,mandibuloacral dysplasia and restrictive dermopathy feature barrier-to-autointegration factor (BAF) nuclear redistribution

Prelamin A processing impairment is a common feature of a restricted group of rare genetic alterations/disorders associated with a wide range of clinical phenotypes. Changes in histone posttranslational modifications, alterations in non-histone chromatin proteins and chromatin disorganization have been specifically linked to impairment of specific, distinct prelamin A processing steps, but the molecular mechanism involved in these processes is not yet understood . In this study, we show that the accumulation of wild-type prelamin A detected in restrictive dermopathy (RD), as well as the accumulation of mutated forms of prelamin A identified in familial partial lipodystrophy (FPLD) and mandibuloacral dysplasia (MADA), affect the nuclear localization of barrier-to-autointegration factor (BAF), a protein able to link lamin A precursor to chromatin remodeling functions. Our findings, in accordance with previously described results, support the hypothesis of a prelamin A involvement in BAF nuclear recruitment and suggest BAF-prelamin A complex as a protein platform usually activated in prelamin A-accumulating diseases. Finally, we demonstrate the involvement of the inner nuclear membrane protein emerin in the proper localization of BAF-prelamin A complex.     

Erythropoietin-induced erythroid differentiation of K562 cells is accompanied by the nuclear translocation of phosphatidylinositol 3-kinase and intranuclear generation of phosphatidylinositol (3,4,5) trisphosphate.

D-3 phosphorylated inositides are a peculiar class of lipids, synthesized by phosphatidylinositol 3-kinase (PtdIns 3-K), which are also present in the nucleus. In order to clarify a possible role for nuclear D-3 phosphorylated inositides during human erythroid differentiation, we have examined the issue of whether or not, in K562 human erythroleukemia cells, erythropoietin (EPO) may generate nuclear translocation of an active PtdIns 3-K. Immunoprecipitation with an anti-p85 regulatory subunit of PtdIns 3-K, revealed that both the intranuclear amount and the activity of the kinase increased rapidly and transiently in response to EPO. Enzyme translocation was blocked by the specific PtdIns 3-K pharmacological inhibitor, LY294002, which also inhibited erythroid differentiation. In vivo, intranuclear synthesis of phosphatidylinositol (3,4,5) trisphosphate (PtdIns (3,4,5)P(3)) was stimulated by EPO. Almost all PtdIns 3-K that translocated to the nucleus was highly phosphorylated on tyrosine residues of the p85 regulatory subunit. These findings strongly suggest that an important step in the signaling pathways that mediate EPO-induced erythroid differentiation may be represented by the intranuclear translocation of an active PtdIns 3-K.